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Cargo.toml

@@ -6,10 +6,11 @@ authors = ["greg <greg.shuflin@protonmail.com>"]
 [dependencies]
 
 schala-repl = { path = "schala-repl" }
-schala-lang = { path = "schala-lang/language" }
-# maaru-lang = { path = "maaru" }
-# rukka-lang = { path = "rukka" }
-# robo-lang = { path = "robo" }
+schala-codegen = { path = "schala-codegen" }
+maaru-lang = { path = "maaru" }
+rukka-lang = { path = "rukka" }
+robo-lang = { path = "robo" }
+schala-lang = { path = "schala-lang" }
 
 [build-dependencies]
 includedir_codegen = "0.2.0"

Grammar

@@ -0,0 +1,31 @@
+
+
+<program> := <statements> EOF
+
+<statements> := <statement>
+             |  <statement> SEP <statements>
+
+<statement> := let <id> = <expr>
+            |  <expr>
+            | <fn_block>
+
+<fn_block> := fn <id> ( <arg_list> ) <statements> end
+
+<arg_list> := e
+           | <id>
+           | <id> , <arg_list>
+
+<expr> := if <expr> then <statements> end
+       |  if <expr> then <statements> else <statements> end
+       |  while <expr> SEP <statements> end
+       |  ( <expr> )
+       |  <binop>
+
+<binop> := <simple_expr>
+        |  <simple_expr> <id> <binop>
+
+<simple_expr> := <id>
+              | <number>
+              | <string>
+
+

README.md

@@ -1,24 +1,21 @@
+
 # Schala - a programming language meta-interpreter
 
-Schala is a Rust framework written to make it easy to create and experiment
-with multipl toy programming languages. It provides a cross-language REPL and
-provisions for tokenizing text, parsing tokens, evaluating an abstract syntax
-tree, and other tasks that are common to all programming languages, as well as sharing state
-between multiple programming languages.
+Schala is a Rust framework written to make it easy to
+create and experiment with toy programming languages. It provides
+a common REPL, and a trait `ProgrammingLanguage` with provisions
+for tokenizing text, parsing tokens, evaluating an abstract syntax tree,
+and other tasks that are common to all programming languages.
 
-Schala is implemented as a Rust library `schala-repl`, which provides a
-function `start_repl`, meant to be used as entry point into a common REPL or
-non-interactive environment. Clients are expected to invoke `start_repl` with a
-vector of programming languages. Individual programming language
-implementations are Rust types that implement the
-`ProgrammingLanguageInterface` trait and store whatever persistent state is
-relevant to that language. 
+Schala is implemented as a Rust library `schala_lib`, which provides a
+`schala_main` function. This function serves as the main loop of the REPL, if run
+interactively, or otherwise reads and interprets programming language source
+files. It expects as input a vector of `PLIGenerator`, which is a type representing
+a closure that returns a boxed trait object that implements the `ProgrammingLanguage` trait,
+and stores any persistent state relevant to that programming language. The ability
+to share state between different programming languages is in the works.
 
-Run schala with: `cargo run`. This will drop you into a REPL environment.  Type
-`:help` for more information, or type in text in any supported programming
-language (currently only schala-lang) to evaluate it in the REPL.
-
-## History
+## About
 
 Schala started out life as an experiment in writing a Javascript-like
 programming language that would never encounter any kind of runtime value
@@ -36,18 +33,18 @@ creating a language name confusingly close to Scala. The naming scheme for
 languages implemented with the Schala meta-interpreter is Chrono Trigger
 characters.
 
-Schala and languages implemented with it are incomplete alpha software and are
-not ready for public release.
+Schala is incomplete alpha software and is not ready for public release.
 
 ## Languages implemented using the meta-interpreter
 
-* The eponymous *Schala* language is a work-in-progress general purpose
-  programming language with static typing and algebraic data types. Its design
-  goals include having a very straightforward implemenation and being syntactically
-  minimal.
+* The eponymous *Schala* language is an interpreted/compiled scripting langauge,
+designed to be relatively simple, but with a reasonably sophisticated type
+system.
 
-* *Maaru* is a very simple dynamically-typed scripting language, with the semantics
-    that all runtime errors return a `null` value rather than fail. 
+* *Maaru* was the original Schala (since renamed to free up the name *Schala*
+  for the above language), a very simple dynamically-typed scripting language
+  such that all possible runtime errors result in null rather than program
+  failure.
 
 * *Robo* is an experiment in creating a lazy, functional, strongly-typed language
 much like Haskell
@@ -59,21 +56,10 @@ much like Haskell
 Here's a partial list of resources I've made use of in the process
 of learning how to write a programming language.
 
-### General
-
-http://thume.ca/2019/04/18/writing-a-compiler-in-rust/
-
 ### Type-checking
 https://skillsmatter.com/skillscasts/10868-inside-the-rust-compiler
 https://www.youtube.com/watch?v=il3gD7XMdmA
 http://dev.stephendiehl.com/fun/006_hindley_milner.html
-https://rust-lang-nursery.github.io/rustc-guide/type-inference.html
-
-https://eli.thegreenplace.net/2018/unification/
-https://eli.thegreenplace.net/2018/type-inference/
-http://smallcultfollowing.com/babysteps/blog/2017/03/25/unification-in-chalk-part-1/
-http://reasonableapproximation.net/2019/05/05/hindley-milner.html
-https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
 
 ### Evaluation
 *Understanding Computation*, Tom Stuart, O'Reilly 2013
@@ -91,5 +77,4 @@ http://blog.ulysse.io/2016/07/03/llvm-getting-started.html
 
 ###Rust resources
 https://thefullsnack.com/en/rust-for-the-web.html
-
 https://rocket.rs/guide/getting-started/

TODO.md

@@ -1,84 +1,24 @@
-# TODO items
 
-## General code cleanup
--experiment with storing metadata via ItemIds on AST nodes (cf. https://rust-lang.github.io/rustc-guide/hir.html, https://github.com/rust-lang/rust/blob/master/src/librustc/hir/mod.rs )
--implement and test open/use statements
--implement field access
-- standardize on an error type that isn't String
--implement a visitor pattern for the use of scope_resolver
+# TODO Items
 
-## Reduction
- - make a good type for actual language builtins to avoid string comparisons
+-make sure to include a :doc command at the REPL that can interface with a lang in a generic way
 
-## Typechecking
+- a subtype is a situation where the compiler is entitled to add a type conversion in the type-checking process
+b/c that type conversion doesn't correspond to a computation 
+    -Sergei W.
 
-- make a type to represent types rather than relying on string comparisons
-
-- look at https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
-
-- cf. the notation mentioned in the cardelli paper, the debug information for the `typechecking` pass should 
-print the generated type variable for every subexpression in an expression
-
-- think about idris-related ideas of multiple implementations of a type for an interface (+ vs * impl for monoids, for preorder/inorder/postorder for Foldable)
-
--should have an Idris-like `cast To From` function
-
-## Schala-lang syntax
-
--idea: the `type` declaration should have some kind of GADT-like syntax
-
-- Idea: if you have a pattern-match where one variant has a variable and the other lacks it
-instead of treating this as a type error, promote the bound variable to an option type
-
-- Include extensible scala-style html"string ${var}" string interpolations
-
-- A neat idea for pattern matching optimization would be if you could match on one of several things in a list
+*A neat idea for pattern matching optimization would be if you could match on one of several things in a list
 ex:
-```if x {
+if x {
  is (comp, LHSPat, RHSPat) if comp in ["==, "<"] -> ...
-}```
+}
 
-- Schala should have both currying *and* default arguments!
-```fn a(b: Int, c:Int, d:Int = 1) -> Int
-    a(1,2) : Int
-    a(1,2,d=2): Int
-    a(_,1,3) : Int -> Int
-    a(1,2, c=_): Int -> Int
-    a(_,_,_) : Int -> Int -> Int -> Int
-```
-
-- scoped types - be able to define a quick enum type scoped to a function or other type for
-  something, that only is meant to be used as a quick bespoke interface between
-  two other things
-
-ex.
-```type enum {
-  type enum MySubVariant {
-    SubVariant1, SubVariant2, etc.
-    }
- Variant1(MySubVariant),
- Variant2(...),
- }```
-
-- inclusive/exclusive range syntax like .. vs ..=
-
-## Compilation
--look into Inkwell for rust LLVM bindings
-
--https://cranelift.readthedocs.io/en/latest/?badge=latest<Paste>
-
-
-## Other links of note
 
 - https://nshipster.com/never/
+-https://cranelift.readthedocs.io/en/latest/?badge=latest<Paste>
+
 -consult http://gluon-lang.org/book/embedding-api.html
 
-
-
-## Playing around with conditional syntax ideas
-
-- 
-
 - if/match playground
 
 simple if
@@ -117,3 +57,70 @@ if the only two guard patterns are true and false, then the abbreviated syntax:
 `'if' discriminator 'then' block_or_expr 'else' block_or_expr`
 can replace `'if' discriminator '{' 'true' 'then' block_or_expr; 'false' 'then' block_or_expr '}'`
 
+
+
+
+- Next priorities: - get ADTs working, get matches working
+
+- inclusive/exclusive range syntax like .. vs ..=
+
+- sketch of an idea for the REPL:
+        -each compiler pass should be a (procedural?) macro like
+        compiler_pass!("parse", dataproducts: ["ast", "parse_tree"], {
+         match parsing::parse(INPUT) {
+           Ok(
+                PASS.add_artifact(
+        }
+
+-should have an Idris-like `cast To From` function
+
+- REPL:
+  - want to be able to do things like `:doc Identifier`, and have the language load up these definitions to the REPL
+
+
+* change 'trait' to 'interface'
+  -think about idris-related ideas of multiple implementations of a type for an interface (+ vs * impl for monoids, for preorder/inorder/postorder for Foldable)
+
+* Share state between programming languages
+
+* idea for Schala - scoped types - be able to define a quick enum type scoped to a function ro something, that only is meant to be used as a quick bespoke interface between two other things
+
+* another idea, allow:
+type enum {
+  type enum MySubVariant {
+    SubVariant1, SubVariant2, etc.
+    }
+ Variant1(MySubVariant),
+ Variant2(...),
+ }
+
+
+
+* idea for Schala: both currying *and* default arguments!
+        ex. fn a(b: Int, c:Int, d:Int = 1) -> Int
+            a(1,2) : Int
+            a(1,2,d=2): Int
+            a(_,1,3) : Int -> Int
+            a(1,2, c=_): Int -> Int
+            a(_,_,_) : Int -> Int -> Int -> Int
+
+
+
+- AST : maybe replace the Expression type with "Ascription(TypeName, Box<Expression>) nodes??
+- parser: add a "debug" field to the Parser struct for all debug-related things
+
+-scala-style html"dfasfsadf${}" string interpolations!
+
+*Compiler passes architecture
+
+-ProgrammingLanguageInterface defines a evaluate_in_repl() and evaluate_no_repl() functions
+-these take in a vec of CompilerPasses
+
+struct CompilerPass {
+        name: String,
+        run: fn(PrevPass) -> NextPass
+}
+
+-change "Type...." names in parser.rs to "Anno..." for non-collision with names in typechecking.rs
+
+-get rid of code pertaining to compilation specifically, have a more generation notion of "execution type"

maaru/src/compilation.rs

@@ -0,0 +1,279 @@
+extern crate llvm_sys;
+
+use std::collections::HashMap;
+
+use self::llvm_sys::prelude::*;
+use self::llvm_sys::{LLVMIntPredicate};
+
+use parser::{AST, Statement, Function, Prototype, Expression, BinOp};
+use schala_repl::LLVMCodeString;
+
+use schala_repl::llvm_wrap as LLVMWrap;
+
+type VariableMap = HashMap<String, LLVMValueRef>;
+
+struct CompilationData {
+    context: LLVMContextRef,
+    module: LLVMModuleRef,
+    builder: LLVMBuilderRef,
+    variables: VariableMap,
+    main_function: LLVMValueRef,
+    current_function: Option<LLVMValueRef>,
+}
+
+pub fn compile_ast(ast: AST) -> LLVMCodeString {
+    println!("Compiling!");
+    let names: VariableMap = HashMap::new();
+
+    let context = LLVMWrap::create_context();
+    let module = LLVMWrap::module_create_with_name("example module");
+    let builder = LLVMWrap::CreateBuilderInContext(context);
+
+    let program_return_type = LLVMWrap::Int64TypeInContext(context);
+    let main_function_type = LLVMWrap::FunctionType(program_return_type, Vec::new(), false);
+    let main_function: LLVMValueRef = LLVMWrap::AddFunction(module, "main", main_function_type);
+
+    let mut data = CompilationData {
+        context: context,
+        builder: builder,
+        module: module,
+        variables: names,
+        main_function: main_function,
+        current_function: None,
+    };
+
+    let bb = LLVMWrap::AppendBasicBlockInContext(data.context, data.main_function, "entry");
+    LLVMWrap::PositionBuilderAtEnd(builder, bb);
+
+    let value = ast.codegen(&mut data);
+
+    LLVMWrap::BuildRet(builder, value);
+
+    let ret = LLVMWrap::PrintModuleToString(module);
+
+    // Clean up. Values created in the context mostly get cleaned up there.
+    LLVMWrap::DisposeBuilder(builder);
+    LLVMWrap::DisposeModule(module);
+    LLVMWrap::ContextDispose(context);
+    LLVMCodeString(ret)
+}
+
+trait CodeGen {
+    fn codegen(&self, &mut CompilationData) -> LLVMValueRef;
+}
+
+impl CodeGen for AST {
+    fn codegen(&self, data: &mut CompilationData) -> LLVMValueRef {
+
+        let int_type = LLVMWrap::Int64TypeInContext(data.context);
+        let mut ret = LLVMWrap::ConstInt(int_type, 0, false);
+
+        for statement in self {
+            ret = statement.codegen(data);
+        }
+        ret
+    }
+}
+
+impl CodeGen for Statement {
+    fn codegen(&self, data: &mut CompilationData) -> LLVMValueRef {
+        use self::Statement::*;
+        match self {
+            &ExprNode(ref expr) => expr.codegen(data),
+            &FuncDefNode(ref func) => func.codegen(data),
+        }
+    }
+}
+
+impl CodeGen for Function {
+    fn codegen(&self, data: &mut CompilationData) -> LLVMValueRef {
+
+        /* should have a check here for function already being defined */
+        let function = self.prototype.codegen(data);
+        let ref body = self.body;
+
+        data.current_function = Some(function);
+
+        let return_type = LLVMWrap::Int64TypeInContext(data.context);
+        let mut ret = LLVMWrap::ConstInt(return_type, 0, false);
+
+        let block = LLVMWrap::AppendBasicBlockInContext(data.context, function, "entry");
+        LLVMWrap::PositionBuilderAtEnd(data.builder, block);
+
+        //insert function params into variables
+        for value in LLVMWrap::GetParams(function) {
+            let name = LLVMWrap::GetValueName(value);
+            data.variables.insert(name, value);
+        }
+
+        for expr in body {
+            ret = expr.codegen(data);
+        }
+
+        LLVMWrap::BuildRet(data.builder, ret);
+
+        // get basic block of main
+        let main_bb = LLVMWrap::GetBasicBlocks(data.main_function).get(0).expect("Couldn't get first block of main").clone();
+        LLVMWrap::PositionBuilderAtEnd(data.builder, main_bb);
+
+        data.current_function = None;
+
+        ret
+    }
+}
+
+impl CodeGen for Prototype {
+    fn codegen(&self, data: &mut CompilationData) -> LLVMValueRef {
+        let num_args = self.parameters.len();
+        let return_type = LLVMWrap::Int64TypeInContext(data.context);
+        let mut arguments: Vec<LLVMTypeRef> = vec![];
+
+        for _ in 0..num_args {
+            arguments.push(LLVMWrap::Int64TypeInContext(data.context));
+        }
+
+        let function_type =
+            LLVMWrap::FunctionType(return_type,
+                                   arguments,
+                                   false);
+
+        let function = LLVMWrap::AddFunction(data.module,
+                                             &*self.name,
+                                             function_type);
+
+        let function_params = LLVMWrap::GetParams(function);
+        for (index, param) in function_params.iter().enumerate() {
+            let name = self.parameters.get(index).expect(&format!("Failed this check at index {}", index));
+            let new = *param;
+
+            LLVMWrap::SetValueName(new, name);
+        }
+
+        function
+    }
+}
+
+impl CodeGen for Expression {
+    fn codegen(&self, data: &mut CompilationData) -> LLVMValueRef {
+        use self::BinOp::*;
+        use self::Expression::*;
+
+        let int_type = LLVMWrap::Int64TypeInContext(data.context);
+        let zero = LLVMWrap::ConstInt(int_type, 0, false);
+
+        match *self {
+            Variable(ref name) => *data.variables.get(&**name).expect(&format!("Can't find variable {}", name)),
+            BinExp(Assign, ref left, ref right) => {
+                if let Variable(ref name) = **left {
+                    let new_value = right.codegen(data);
+                    data.variables.insert((**name).clone(), new_value);
+                    new_value
+                } else {
+                    panic!("Bad variable assignment")
+                }
+            }
+            BinExp(ref op, ref left, ref right) => {
+                let lhs = left.codegen(data);
+                let rhs = right.codegen(data);
+                op.codegen_with_ops(data, lhs, rhs)
+            }
+            Number(ref n) => {
+                let native_val = *n as u64;
+                let int_value: LLVMValueRef = LLVMWrap::ConstInt(int_type, native_val, false);
+                int_value
+            }
+            Conditional(ref test, ref then_expr, ref else_expr) => {
+                let condition_value = test.codegen(data);
+                let is_nonzero =
+                    LLVMWrap::BuildICmp(data.builder,
+                                        LLVMIntPredicate::LLVMIntNE,
+                                        condition_value,
+                                        zero,
+                                        "ifcond");
+
+                let func = LLVMWrap::GetBasicBlockParent(LLVMWrap::GetInsertBlock(data.builder));
+
+                let mut then_block =
+                    LLVMWrap::AppendBasicBlockInContext(data.context, func, "then_block");
+                let mut else_block =
+                    LLVMWrap::AppendBasicBlockInContext(data.context, func, "else_block");
+                let merge_block =
+                    LLVMWrap::AppendBasicBlockInContext(data.context, func, "ifcont");
+
+                // add conditional branch to ifcond block
+                LLVMWrap::BuildCondBr(data.builder, is_nonzero, then_block, else_block);
+
+                // start inserting into then block
+                LLVMWrap::PositionBuilderAtEnd(data.builder, then_block);
+
+                // then-block codegen
+                let then_return = then_expr.codegen(data);
+                LLVMWrap::BuildBr(data.builder, merge_block);
+
+                // update then block b/c recursive codegen() call may have changed the notion of
+                // the current block
+                then_block = LLVMWrap::GetInsertBlock(data.builder);
+
+                // then do the same stuff again for the else branch
+                //
+                LLVMWrap::PositionBuilderAtEnd(data.builder, else_block);
+                let else_return = match *else_expr {
+                    Some(ref e) => e.codegen(data),
+                    None => zero,
+                };
+                LLVMWrap::BuildBr(data.builder, merge_block);
+                else_block = LLVMWrap::GetInsertBlock(data.builder);
+
+                LLVMWrap::PositionBuilderAtEnd(data.builder, merge_block);
+
+                let phi = LLVMWrap::BuildPhi(data.builder, int_type, "phinode");
+                let values = vec![then_return, else_return];
+                let blocks = vec![then_block, else_block];
+                LLVMWrap::AddIncoming(phi, values, blocks);
+                phi
+            }
+            Block(ref exprs) => {
+                let mut ret = zero;
+                for e in exprs.iter() {
+                    ret = e.codegen(data);
+                }
+                ret
+            }
+            ref e => {
+                println!("Unimplemented {:?}", e);
+                unimplemented!()
+            }
+        }
+    }
+}
+
+impl BinOp {
+    fn codegen_with_ops(&self, data: &CompilationData, lhs: LLVMValueRef, rhs: LLVMValueRef) -> LLVMValueRef {
+        use self::BinOp::*;
+        macro_rules! simple_binop {
+            ($fnname: expr, $name: expr) => {
+                $fnname(data.builder, lhs, rhs, $name)
+            }
+        }
+        let int_type = LLVMWrap::Int64TypeInContext(data.context);
+        match *self {
+            Add => simple_binop!(LLVMWrap::BuildAdd, "addtemp"),
+            Sub => simple_binop!(LLVMWrap::BuildSub, "subtemp"),
+            Mul => simple_binop!(LLVMWrap::BuildMul, "multemp"),
+            Div => simple_binop!(LLVMWrap::BuildUDiv, "divtemp"),
+            Mod => simple_binop!(LLVMWrap::BuildSRem, "remtemp"),
+            Less => {
+                let pred: LLVMValueRef =
+                    LLVMWrap::BuildICmp(data.builder, LLVMIntPredicate::LLVMIntULT, lhs, rhs, "tmp");
+                LLVMWrap::BuildZExt(data.builder, pred, int_type, "temp")
+            }
+            Greater => {
+                let pred: LLVMValueRef =
+                    LLVMWrap::BuildICmp(data.builder, LLVMIntPredicate::LLVMIntUGT, lhs, rhs, "tmp");
+                LLVMWrap::BuildZExt(data.builder, pred, int_type, "temp")
+            }
+            ref unknown => panic!("Bad operator {:?}", unknown),
+        }
+    }
+}
+

maaru/src/lib.rs

@@ -5,6 +5,9 @@ extern crate schala_repl;
 mod tokenizer;
 mod parser;
 mod eval;
+mod compilation;
+
+use schala_repl::{ProgrammingLanguageInterface, EvalOptions, UnfinishedComputation, FinishedComputation, TraceArtifact};
 
 #[derive(Debug)]
 pub struct TokenError {
@@ -31,42 +34,6 @@ impl<'a> Maaru<'a> {
   }
 }
 
-/*
-fn execute_pipeline(&mut self, input: &str, options: &EvalOptions) -> Result<String, String> {
-  let mut output = UnfinishedComputation::default();
-
-  let tokens = match tokenizer::tokenize(input) {
-    Ok(tokens) => {
-      if let Some(_) = options.debug_passes.get("tokens") {
-        output.add_artifact(TraceArtifact::new("tokens", format!("{:?}", tokens)));
-      }
-      tokens
-    },
-    Err(err) => {
-      return output.finish(Err(format!("Tokenization error: {:?}\n", err.msg)))
-    }
-  };
-
-  let ast = match parser::parse(&tokens, &[]) {
-    Ok(ast) => {
-      if let Some(_) = options.debug_passes.get("ast") {
-        output.add_artifact(TraceArtifact::new("ast", format!("{:?}", ast)));
-      }
-      ast
-    },
-    Err(err) => {
-      return output.finish(Err(format!("Parse error: {:?}\n", err.msg)))
-    }
-  };
-  let mut evaluation_output = String::new();
-  for s in self.evaluator.run(ast).iter() {
-    evaluation_output.push_str(s);
-  }
-  Ok(evaluation_output)
-}
-*/
-
-/*
 impl<'a> ProgrammingLanguageInterface for Maaru<'a> {
   fn get_language_name(&self) -> String {
     "Maaru".to_string()
@@ -74,5 +41,63 @@ impl<'a> ProgrammingLanguageInterface for Maaru<'a> {
   fn get_source_file_suffix(&self) -> String {
     format!("maaru")
   }
-}
+
+  fn execute_pipeline(&mut self, input: &str, options: &EvalOptions) -> FinishedComputation {
+    let mut output = UnfinishedComputation::default();
+
+    let tokens = match tokenizer::tokenize(input) {
+      Ok(tokens) => {
+        if let Some(_) = options.debug_passes.get("tokens") {
+          output.add_artifact(TraceArtifact::new("tokens", format!("{:?}", tokens)));
+        }
+        tokens
+      },
+      Err(err) => {
+        return output.finish(Err(format!("Tokenization error: {:?}\n", err.msg)))
+      }
+    };
+
+    let ast = match parser::parse(&tokens, &[]) {
+      Ok(ast) => {
+        if let Some(_) = options.debug_passes.get("ast") {
+          output.add_artifact(TraceArtifact::new("ast", format!("{:?}", ast)));
+        }
+        ast
+      },
+      Err(err) => {
+        return output.finish(Err(format!("Parse error: {:?}\n", err.msg)))
+      }
+    };
+    let mut evaluation_output = String::new();
+    for s in self.evaluator.run(ast).iter() {
+      evaluation_output.push_str(s);
+    }
+    output.finish(Ok(evaluation_output))
+  }
+
+  /* TODO make this work with new framework */
+  /*
+  fn can_compile(&self) -> bool {
+    true
+  }
+
+  fn compile(&mut self, input: &str) -> LLVMCodeString {
+    let tokens = match tokenizer::tokenize(input) {
+      Ok(tokens) =>  tokens,
+      Err(err) => {
+        let msg = format!("Tokenization error: {:?}\n", err.msg);
+        panic!("{}", msg);
+      }
+    };
+
+    let ast = match parser::parse(&tokens, &[]) {
+      Ok(ast) => ast,
+      Err(err) => {
+        let msg = format!("Parse error: {:?}\n", err.msg);
+        panic!("{}", msg);
+      }
+    };
+    compilation::compile_ast(ast)
+  }
   */
+}

robo/src/lib.rs

@@ -4,7 +4,7 @@ extern crate itertools;
 extern crate schala_repl;
 
 use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface, EvalOptions}; 
+use schala_repl::{ProgrammingLanguageInterface, EvalOptions, FinishedComputation, UnfinishedComputation};
 
 pub struct Robo {
 }
@@ -154,5 +154,17 @@ impl ProgrammingLanguageInterface for Robo {
   fn get_source_file_suffix(&self) -> String {
     format!("robo")
   }
+
+  fn execute_pipeline(&mut self, input: &str, _eval_options: &EvalOptions) -> FinishedComputation {
+    let output = UnfinishedComputation::default();
+    let tokens = match tokenize(input) {
+      Ok(tokens) => tokens,
+      Err(e) => {
+        return output.finish(Err(format!("Tokenize error: {:?}", e)));
+      }
+    };
+
+    output.finish(Ok(format!("{:?}", tokens)))
+  }
 }
 

rukka/src/lib.rs

@@ -4,7 +4,7 @@ extern crate itertools;
 extern crate schala_repl;
 
 use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface, EvalOptions};
+use schala_repl::{ProgrammingLanguageInterface, EvalOptions, UnfinishedComputation, FinishedComputation};
 use std::iter::Peekable;
 use std::vec::IntoIter;
 use std::str::Chars;
@@ -72,6 +72,24 @@ impl ProgrammingLanguageInterface for Rukka {
   fn get_source_file_suffix(&self) -> String {
     format!("rukka")
   }
+
+  fn execute_pipeline(&mut self, input: &str, _eval_options: &EvalOptions) -> FinishedComputation {
+    let output = UnfinishedComputation::default();
+    let sexps = match read(input) {
+      Err(err) => {
+        return output.finish(Err(format!("Error: {}", err)));
+      },
+      Ok(sexps) => sexps
+    };
+
+    let output_str: String = sexps.into_iter().enumerate().map(|(i, sexp)| {
+      match self.state.eval(sexp) {
+        Ok(result) => format!("{}: {}", i, result.print()),
+        Err(err) => format!("{} Error: {}", i, err),
+      }
+    }).intersperse(format!("\n")).collect();
+    output.finish(Ok(output_str))
+  }
 }
 
 impl EvaluatorState {

schala-codegen/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "schala-codegen"
+version = "0.1.0"
+authors = ["greg <greg.shuflin@protonmail.com>"]
+
+[dependencies]
+syn = { version = "0.13.1", features = ["full", "extra-traits"] }
+quote = "0.5"
+schala-repl = { path = "../schala-repl" }
+
+[lib]
+proc-macro = true

schala-codegen/src/lib.rs

@@ -0,0 +1,102 @@
+#![feature(trace_macros)]
+#![feature(proc_macro)]
+extern crate proc_macro;
+#[macro_use]
+extern crate quote;
+extern crate syn;
+
+extern crate schala_repl;
+
+use proc_macro::TokenStream;
+use syn::{Ident, Attribute, DeriveInput};
+
+fn extract_attribute_arg_by_name(name: &str, attrs: &Vec<Attribute>) -> Option<String> {
+  use syn::{Meta, Lit, MetaNameValue};
+  attrs.iter().map(|attr| attr.interpret_meta()).find(|meta| {
+    match meta {
+      &Some(Meta::NameValue(MetaNameValue { ident, .. })) if ident.as_ref() == name => true,
+      _ => false
+    }
+  }).and_then(|meta| {
+    match meta {
+      Some(Meta::NameValue(MetaNameValue { lit: Lit::Str(litstr), .. })) => Some(litstr.value()),
+      _ => None,
+    }
+  })
+}
+
+fn extract_attribute_list(name: &str, attrs: &Vec<Attribute>) -> Option<Vec<(Ident, Option<Vec<Ident>>)>> {
+  use syn::{Meta, MetaList, NestedMeta};
+  attrs.iter().find(|attr| {
+    match attr.path.segments.iter().nth(0) {
+      Some(segment) if segment.ident.as_ref() == name => true,
+      _ => false
+    }
+  }).and_then(|attr| {
+    match attr.interpret_meta() {
+      Some(Meta::List(MetaList { nested, .. })) => {
+        Some(nested.iter().map(|nested_meta| match nested_meta {
+          &NestedMeta::Meta(Meta::Word(ident)) => (ident, None),
+          &NestedMeta::Meta(Meta::List(MetaList { ident, nested: ref nested2, .. })) => {
+            let own_args = nested2.iter().map(|nested_meta2| match nested_meta2 {
+              &NestedMeta::Meta(Meta::Word(ident)) => ident,
+              _ => panic!("Bad format for doubly-nested attribute list")
+            }).collect();
+            (ident, Some(own_args))
+          },
+          _ => panic!("Bad format for nested list")
+        }).collect())
+      },
+      _ => panic!("{} must be a comma-delimited list surrounded by parens", name)
+    }
+  })
+}
+
+#[proc_macro_derive(ProgrammingLanguageInterface, attributes(LanguageName, SourceFileExtension, PipelineSteps))]
+pub fn derive_programming_language_interface(input: TokenStream) -> TokenStream {
+  let ast: DeriveInput = syn::parse(input).unwrap();
+  let name = &ast.ident;
+  let attrs = &ast.attrs;
+
+  let language_name: String = extract_attribute_arg_by_name("LanguageName", attrs).expect("LanguageName is required");
+  let file_ext = extract_attribute_arg_by_name("SourceFileExtension", attrs).expect("SourceFileExtension is required");
+  let passes = extract_attribute_list("PipelineSteps", attrs).expect("PipelineSteps are required");
+  let pass_idents = passes.iter().map(|x| x.0);
+
+  //let pass_names: Vec<String> = passes.iter().map(|pass| pass.0.to_string()).collect();
+  let pass_descriptors = passes.iter().map(|pass| {
+    let name = pass.0.to_string();
+    let opts: Vec<String> = match &pass.1 {
+      None => vec![],
+      Some(opts) => opts.iter().map(|o| o.to_string()).collect(),
+    };
+
+    quote! {
+      PassDescriptor {
+        name: #name.to_string(),
+        debug_options: vec![#(format!(#opts)),*]
+      }
+    }
+  });
+
+  let tokens = quote! {
+    use schala_repl::PassDescriptor;
+    impl ProgrammingLanguageInterface for #name {
+      fn get_language_name(&self) -> String {
+        #language_name.to_string()
+      }
+      fn get_source_file_suffix(&self) -> String {
+        #file_ext.to_string()
+      }
+      fn execute_pipeline(&mut self, input: &str, options: &EvalOptions) -> FinishedComputation {
+        let mut chain = pass_chain![self, options; #(#pass_idents),* ];
+        chain(input)
+      }
+      fn get_passes(&self) -> Vec<PassDescriptor> {
+        vec![ #(#pass_descriptors),* ]
+        //vec![ #(PassDescriptor { name: #pass_names.to_string(), debug_options: vec![] }),* ]
+      }
+    }
+  };
+  tokens.into()
+}

schala-lang/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "schala-lang"
+version = "0.1.0"
+authors = ["greg <greg.shuflin@protonmail.com>"]
+
+[dependencies]
+itertools = "0.5.8"
+take_mut = "0.1.3"
+maplit = "*"
+lazy_static = "0.2.8"
+
+schala-repl = { path = "../schala-repl" }
+schala-codegen = { path = "../schala-codegen" }

schala-lang/codegen/Cargo.toml

@@ -1,12 +0,0 @@
-[package]
-name = "schala-lang-codegen"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
-
-[lib]
-proc-macro = true
-
-[dependencies]
-syn = { version = "0.15.12", features = ["full", "extra-traits", "fold"] }
-quote = "0.6.8"

schala-lang/codegen/src/lib.rs

@@ -1,50 +0,0 @@
-#![feature(box_patterns)]
-#![recursion_limit="128"]
-extern crate proc_macro;
-#[macro_use]
-extern crate quote;
-#[macro_use]
-extern crate syn;
-
-use self::proc_macro::TokenStream;
-use self::syn::fold::Fold;
-
-struct RecursiveDescentFn {
-}
-
-impl Fold for RecursiveDescentFn {
-  fn fold_item_fn(&mut self, mut i: syn::ItemFn) -> syn::ItemFn {
-    let box block = i.block;
-    let ref ident = i.ident;
-
-    let new_block: syn::Block = parse_quote! {
-      {
-        let next_token_before_parse = self.token_handler.peek();
-        let record = ParseRecord {
-          production_name: stringify!(#ident).to_string(),
-          next_token: format!("{}", next_token_before_parse.to_string_with_metadata()),
-          level: self.parse_level,
-        };
-        self.parse_level += 1;
-        self.parse_record.push(record);
-        let result = { #block };
-
-        if self.parse_level != 0 {
-          self.parse_level -= 1;
-        }
-        result
-      }
-    };
-    i.block = Box::new(new_block);
-    i
-  }
-}
-
-#[proc_macro_attribute]
-pub fn recursive_descent_method(_attr: TokenStream, item: TokenStream) -> TokenStream {
-
-  let input: syn::ItemFn = parse_macro_input!(item as syn::ItemFn);
-  let mut folder = RecursiveDescentFn {};
-  let output = folder.fold_item_fn(input);
-  TokenStream::from(quote!(#output))
-}

schala-lang/language/Cargo.toml

@@ -1,18 +0,0 @@
-[package]
-name = "schala-lang"
-version = "0.1.0"
-authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
-
-[dependencies]
-itertools = "0.8.0"
-take_mut = "0.2.2"
-maplit = "1.0.1"
-lazy_static = "1.3.0"
-failure = "0.1.5"
-ena = "0.11.0"
-stopwatch = "0.0.7"
-derivative = "1.0.3"
-
-schala-lang-codegen = { path = "../codegen" }
-schala-repl = { path = "../../schala-repl" }

schala-lang/language/src/ast.rs

@@ -1,310 +0,0 @@
-use std::rc::Rc;
-use std::convert::From;
-
-use crate::derivative::Derivative;
-use crate::symbol_table::FullyQualifiedSymbolName;
-
-mod operators;
-pub use operators::*;
-
-/// An abstract identifier for an AST node
-#[derive(Debug, PartialEq, Eq, Hash, Clone)]
-pub struct ItemId {
-  idx: u32,
-}
-
-impl ItemId {
-  fn new(n: u32) -> ItemId {
-    ItemId { idx: n }
-  }
-}
-
-pub struct ItemIdStore {
-  last_idx: u32
-}
-
-impl ItemIdStore {
-  pub fn new() -> ItemIdStore {
-    ItemIdStore { last_idx: 0 }
-  }
-  /// Always returns an ItemId with internal value zero
-  #[cfg(test)]
-  pub fn new_id() -> ItemId {
-    ItemId { idx: 0 }
-  }
-
-  /// This limits the size of the AST to 2^32 tree elements
-  pub fn fresh(&mut self) -> ItemId {
-    let idx = self.last_idx;
-    self.last_idx += 1;
-    ItemId::new(idx)
-  }
-}
-
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct Meta<T> {
-  pub n: T,
-  pub fqsn: Option<FullyQualifiedSymbolName>
-}
-
-impl<T> Meta<T> {
-  pub fn new(n: T) -> Meta<T> {
-    Meta { n,
-    fqsn: None,
-    }
-  }
-
-  pub fn node(&self) -> &T {
-    &self.n
-  }
-
-  pub fn mut_node(&mut self) -> &mut T {
-    &mut self.n
-  }
-}
-
-//TODO this PartialEq is here to make tests work - find a way to make it not necessary
-#[derive(Clone, Debug, Default, PartialEq)]
-struct SourceMap {
-}
-
-impl From<Expression> for Meta<Expression> {
-  fn from(expr: Expression) -> Meta<Expression> {
-    Meta::new(expr)
-  }
-}
-
-#[derive(Derivative, Debug)]
-#[derivative(PartialEq)]
-pub struct AST {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub statements: Vec<Statement>
-}
-
-#[derive(Derivative, Debug, Clone)]
-#[derivative(PartialEq)]
-pub struct Statement {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub kind: StatementKind,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum StatementKind {
-  Expression(Expression),
-  Declaration(Declaration), //TODO Declaration should also be Meta-wrapped; only Expression and Declaration are Meta-wrapped maybe?
-}
-
-pub type Block = Vec<Statement>;
-pub type ParamName = Rc<String>;
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct QualifiedName {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub components: Vec<Rc<String>>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct FormalParam {
-  pub name: ParamName,
-  pub default: Option<Expression>,
-  pub anno: Option<TypeIdentifier>
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Declaration {
-  FuncSig(Signature),
-  FuncDecl(Signature, Block),
-  TypeDecl {
-    name: TypeSingletonName,
-    body: TypeBody,
-    mutable: bool
-  },
-  TypeAlias(Rc<String>, Rc<String>), //should have TypeSingletonName in it, or maybe just String, not sure
-  Binding {
-    name: Rc<String>,
-    constant: bool,
-    type_anno: Option<TypeIdentifier>,
-    expr: Expression,
-  },
-  Impl {
-    type_name: TypeIdentifier,
-    interface_name: Option<TypeSingletonName>,
-    block: Vec<Declaration>,
-  },
-  Interface {
-    name: Rc<String>,
-    signatures: Vec<Signature>
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct Signature {
-  pub name: Rc<String>,
-  pub operator: bool,
-  pub params: Vec<FormalParam>,
-  pub type_anno: Option<TypeIdentifier>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct TypeBody(pub Vec<Variant>);
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Variant {
-  UnitStruct(Rc<String>),
-  TupleStruct(Rc<String>, Vec<TypeIdentifier>),
-  Record {
-    name: Rc<String>,
-    members: Vec<(Rc<String>, TypeIdentifier)>,
-  }
-}
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct Expression {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub kind: ExpressionKind,
-  pub type_anno: Option<TypeIdentifier>
-}
-
-impl Expression {
-  pub fn new(id: ItemId, kind: ExpressionKind) -> Expression {
-    Expression { id, kind, type_anno: None }
-  }
-
-  pub fn with_anno(id: ItemId, kind: ExpressionKind, type_anno: TypeIdentifier) -> Expression {
-    Expression { id, kind, type_anno: Some(type_anno) }
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum TypeIdentifier {
-  Tuple(Vec<TypeIdentifier>),
-  Singleton(TypeSingletonName)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct TypeSingletonName {
-  pub name: Rc<String>,
-  pub params: Vec<TypeIdentifier>,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ExpressionKind {
-  NatLiteral(u64),
-  FloatLiteral(f64),
-  StringLiteral(Rc<String>),
-  BoolLiteral(bool),
-  BinExp(BinOp, Box<Expression>, Box<Expression>),
-  PrefixExp(PrefixOp, Box<Expression>),
-  TupleLiteral(Vec<Expression>),
-  Value(QualifiedName),
-  NamedStruct {
-    name: QualifiedName,
-    fields: Vec<(Rc<String>, Expression)>,
-  },
-  Call {
-    f: Box<Expression>,
-    arguments: Vec<InvocationArgument>,
-  },
-  Index {
-    indexee: Box<Expression>,
-    indexers: Vec<Expression>,
-  },
-  IfExpression {
-    discriminator: Box<Discriminator>,
-    body: Box<IfExpressionBody>,
-  },
-  WhileExpression {
-    condition: Option<Box<Expression>>,
-    body: Block,
-  },
-  ForExpression {
-    enumerators: Vec<Enumerator>,
-    body: Box<ForBody>,
-  },
-  Lambda {
-    params: Vec<FormalParam>,
-    type_anno: Option<TypeIdentifier>,
-    body: Block,
-  },
-  ListLiteral(Vec<Expression>),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum InvocationArgument {
-  Positional(Expression),
-  Keyword {
-    name: Rc<String>,
-    expr: Expression,
-  },
-  Ignored
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Discriminator {
-  Simple(Expression),
-  BinOp(Expression, BinOp)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum IfExpressionBody {
-  SimpleConditional(Block, Option<Block>),
-  SimplePatternMatch(Pattern, Block, Option<Block>),
-  GuardList(Vec<GuardArm>)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct GuardArm {
-  pub guard: Guard,
-  pub body: Block,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Guard {
-  Pat(Pattern),
-  HalfExpr(HalfExpr)
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct HalfExpr {
-  pub op: Option<BinOp>,
-  pub expr: ExpressionKind,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum Pattern {
-  Ignored,
-  TuplePattern(Vec<Pattern>),
-  Literal(PatternLiteral),
-  TupleStruct(QualifiedName, Vec<Pattern>),
-  Record(QualifiedName, Vec<(Rc<String>, Pattern)>),
-  VarOrName(QualifiedName),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum PatternLiteral {
-  NumPattern {
-    neg: bool,
-    num: ExpressionKind,
-  },
-  StringPattern(Rc<String>),
-  BoolPattern(bool),
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct Enumerator {
-  pub id: Rc<String>,
-  pub generator: Expression,
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ForBody {
-  MonadicReturn(Expression),
-  StatementBlock(Block),
-}

schala-lang/language/src/ast/operators.rs

@@ -1,112 +0,0 @@
-use std::rc::Rc;
-use std::str::FromStr;
-
-use crate::tokenizing::TokenKind;
-use crate::builtin::Builtin;
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct PrefixOp {
-  sigil: Rc<String>,
-  pub builtin: Option<Builtin>,
-}
-
-impl PrefixOp {
-  #[allow(dead_code)]
-  pub fn sigil(&self) -> &Rc<String> {
-    &self.sigil
-  }
-  pub fn is_prefix(op: &str) -> bool {
-    match op {
-      "+" => true,
-      "-" => true,
-      "!" => true,
-      _ => false
-    }
-  }
-}
-
-impl FromStr for PrefixOp {
-  type Err = ();
-
-  fn from_str(s: &str) -> Result<Self, Self::Err> {
-    use Builtin::*;
-
-    let builtin = match s {
-      "+" => Ok(Increment),
-      "-" => Ok(Negate),
-      "!" => Ok(BooleanNot),
-      _ => Err(())
-    };
-
-    builtin.map(|builtin| PrefixOp { sigil: Rc::new(s.to_string()), builtin: Some(builtin) })
-  }
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct BinOp {
-  sigil: Rc<String>,
-  pub builtin: Option<Builtin>,
-}
-
-impl BinOp {
-  pub fn from_sigil(sigil: &str) -> BinOp {
-    let builtin = Builtin::from_str(sigil).ok();
-    BinOp { sigil: Rc::new(sigil.to_string()), builtin }
-  }
-  pub fn sigil(&self) -> &Rc<String> {
-    &self.sigil
-  }
-  pub fn from_sigil_token(tok: &TokenKind) -> Option<BinOp> {
-    let s = token_kind_to_sigil(tok)?;
-    Some(BinOp::from_sigil(s))
-  }
-
-  pub fn min_precedence() -> i32 {
-    i32::min_value()
-  }
-  pub fn get_precedence_from_token(op_tok: &TokenKind) -> Option<i32> {
-    let s = token_kind_to_sigil(op_tok)?;
-    Some(binop_precedences(s))
-  }
-
-  pub fn get_precedence(&self) -> i32 {
-    binop_precedences(&self.sigil)
-  }
-}
-
-fn token_kind_to_sigil<'a>(tok: &'a TokenKind) -> Option<&'a str> {
-  use self::TokenKind::*;
-  Some(match tok {
-    Operator(op) => op.as_str(),
-    Period => ".",
-    Pipe => "|",
-    Slash => "/",
-    LAngleBracket => "<",
-    RAngleBracket => ">",
-    Equals => "=",
-    _ => return None
-  })
-}
-
-fn binop_precedences(s: &str) -> i32 {
-  let default = 10_000_000;
-  match s {
-    "+" => 10,
-    "-" => 10,
-    "*" =>  20,
-    "/" =>  20,
-    "%" =>  20,
-    "++" => 30,
-    "^" =>  30,
-    "&" =>  20,
-    "|" => 20,
-    ">" => 20,
-    ">=" => 20,
-    "<" =>  20,
-    "<=" => 20,
-    "==" => 40,
-    "=" =>  10,
-    "<=>" => 30,
-    _ => default,
-  }
-}

schala-lang/language/src/builtin.rs

@@ -1,102 +0,0 @@
-use std::str::FromStr;
-
-use crate::typechecking::{TypeConst, Type};
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub enum Builtin {
-  Add,
-  Increment,
-  Subtract,
-  Negate,
-  Multiply,
-  Divide,
-  Quotient,
-  Modulo,
-  Exponentiation,
-  BitwiseAnd,
-  BitwiseOr,
-  BooleanAnd,
-  BooleanOr,
-  BooleanNot,
-  Equality,
-  LessThan,
-  LessThanOrEqual,
-  GreaterThan,
-  GreaterThanOrEqual,
-  Comparison,
-  FieldAccess,
-  IOPrint,
-  IOPrintLn,
-  IOGetLine,
-  Assignment,
-  Concatenate,
-}
-
-impl Builtin {
-  pub fn get_type(&self) -> Type {
-    use Builtin::*;
-    match self {
-      Add => ty!(Nat -> Nat -> Nat),
-      Subtract => ty!(Nat -> Nat -> Nat),
-      Multiply => ty!(Nat -> Nat -> Nat),
-      Divide => ty!(Nat -> Nat -> Float),
-      Quotient => ty!(Nat -> Nat -> Nat),
-      Modulo => ty!(Nat -> Nat -> Nat),
-      Exponentiation => ty!(Nat -> Nat -> Nat),
-      BitwiseAnd => ty!(Nat -> Nat -> Nat),
-      BitwiseOr => ty!(Nat -> Nat -> Nat),
-      BooleanAnd => ty!(Bool -> Bool -> Bool),
-      BooleanOr => ty!(Bool -> Bool -> Bool),
-      BooleanNot => ty!(Bool -> Bool),
-      Equality => ty!(Nat -> Nat -> Bool),
-      LessThan => ty!(Nat -> Nat -> Bool),
-      LessThanOrEqual => ty!(Nat -> Nat -> Bool),
-      GreaterThan => ty!(Nat -> Nat -> Bool),
-      GreaterThanOrEqual => ty!(Nat -> Nat -> Bool),
-      Comparison => ty!(Nat -> Nat -> Ordering),
-      FieldAccess => ty!(Unit),
-      IOPrint => ty!(Unit),
-      IOPrintLn => ty!(Unit) ,
-      IOGetLine => ty!(StringT),
-      Assignment => ty!(Unit),
-      Concatenate => ty!(StringT -> StringT -> StringT),
-      Increment => ty!(Nat -> Int),
-      Negate => ty!(Nat -> Int)
-    }
-  }
-}
-
-impl FromStr for Builtin {
-  type Err = ();
-
-  fn from_str(s: &str) -> Result<Self, Self::Err> {
-    use Builtin::*;
-    Ok(match s {
-      "+" => Add,
-      "-" => Subtract,
-      "*" => Multiply,
-      "/" => Divide,
-      "quot" => Quotient,
-      "%" => Modulo,
-      "++" => Concatenate,
-      "^" =>  Exponentiation,
-      "&" => BitwiseAnd,
-      "&&" => BooleanAnd,
-      "|" => BitwiseOr,
-      "||" => BooleanOr,
-      "!" => BooleanNot,
-      ">" => GreaterThan,
-      ">=" => GreaterThanOrEqual,
-      "<" => LessThan,
-      "<=" => LessThanOrEqual,
-      "==" => Equality,
-      "=" => Assignment,
-      "<=>" => Comparison,
-      "." => FieldAccess,
-      "print" => IOPrint,
-      "println" => IOPrintLn,
-      "getline" => IOGetLine,
-      _ => return Err(())
-    })
-  }
-}

schala-lang/language/src/debugging.rs

@@ -1,10 +0,0 @@
-use crate::ast::*;
-
-impl AST {
-  pub fn compact_debug(&self) -> String {
-    format!("{:?}", self)
-  }
-  pub fn expanded_debug(&self) -> String {
-    format!("{:#?}", self)
-  }
-}

schala-lang/language/src/eval.rs

@@ -1,502 +0,0 @@
-
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::fmt::Write;
-use std::io;
-
-use itertools::Itertools;
-
-use crate::util::ScopeStack;
-use crate::reduced_ast::{BoundVars, ReducedAST, Stmt, Expr, Lit, Func, Alternative, Subpattern};
-use crate::symbol_table::{SymbolSpec, Symbol, SymbolTable, ScopeSegment, ScopeSegmentKind, FullyQualifiedSymbolName};
-use crate::builtin::Builtin;
-
-mod test;
-
-pub struct State<'a> {
-  values: ScopeStack<'a, Rc<String>, ValueEntry>,
-  symbol_table_handle: Rc<RefCell<SymbolTable>>,
-}
-
-impl<'a> State<'a> {
-  pub fn new(symbol_table_handle: Rc<RefCell<SymbolTable>>) -> State<'a> {
-    let values = ScopeStack::new(Some(format!("global")));
-    State { values, symbol_table_handle }
-  }
-
-  pub fn debug_print(&self) -> String {
-    format!("Values: {:?}", self.values)
-  }
-
-  fn new_frame(&'a self, items: &'a Vec<Node>, bound_vars: &BoundVars) -> State<'a> {
-    let mut inner_state = State {
-      values: self.values.new_scope(None),
-      symbol_table_handle: self.symbol_table_handle.clone(),
-    };
-    for (bound_var, val) in bound_vars.iter().zip(items.iter()) {
-      if let Some(bv) = bound_var.as_ref() {
-        inner_state.values.insert(bv.clone(), ValueEntry::Binding { constant: true, val: val.clone() });
-      }
-    }
-    inner_state
-  }
-}
-
-#[derive(Debug, Clone)]
-enum Node {
-  Expr(Expr),
-  PrimObject {
-    name: Rc<String>,
-    tag: usize,
-    items: Vec<Node>,
-  },
-  PrimTuple {
-    items: Vec<Node>
-  }
-}
-
-fn paren_wrapped_vec(terms: impl Iterator<Item=String>) -> String {
-  let mut buf = String::new();
-  write!(buf, "(").unwrap();
-  for term in terms.map(|e| Some(e)).intersperse(None) {
-    match term {
-      Some(e) => write!(buf, "{}", e).unwrap(),
-      None => write!(buf, ", ").unwrap(),
-    };
-  }
-  write!(buf, ")").unwrap();
-  buf
-}
-
-
-impl Node {
-  fn to_repl(&self, symbol_table: &SymbolTable) -> String {
-    match self {
-      Node::Expr(e) => e.to_repl(symbol_table),
-      Node::PrimObject { name, items, .. } if items.len() == 0 => format!("{}", name),
-      Node::PrimObject { name, items, .. } => format!("{}{}", name, paren_wrapped_vec(items.iter().map(|x| x.to_repl(symbol_table)))),
-      Node::PrimTuple { items } => format!("{}", paren_wrapped_vec(items.iter().map(|x| x.to_repl(symbol_table)))),
-    }
-  }
-  fn is_true(&self) -> bool {
-    match self {
-      Node::Expr(Expr::Lit(crate::reduced_ast::Lit::Bool(true))) => true,
-      _ => false,
-    }
-  }
-}
-
-#[derive(Debug)]
-enum ValueEntry {
-  Binding {
-    constant: bool,
-    val: /*FullyEvaluatedExpr*/ Node, //TODO make this use a subtype to represent fully evaluatedness
-  }
-}
-
-type EvalResult<T> = Result<T, String>;
-
-impl Expr {
-  fn to_node(self) -> Node {
-    Node::Expr(self)
-  }
-  fn to_repl(&self, symbol_table: &SymbolTable) -> String {
-    use self::Lit::*;
-    use self::Func::*;
-
-    let _ = symbol_table;
-
-    match self {
-      Expr::Lit(ref l) => match l {
-        Nat(n) => format!("{}", n),
-        Int(i) => format!("{}", i),
-        Float(f) => format!("{}", f),
-        Bool(b) => format!("{}", b),
-        StringLit(s) => format!("\"{}\"", s),
-      },
-      Expr::Func(f) => match f {
-        BuiltIn(builtin) => format!("<built-in function '{:?}'>", builtin),
-        UserDefined { name: None, .. } => format!("<function>"),
-        UserDefined { name: Some(name), .. } => format!("<function '{}'>", name),
-      },
-      Expr::Constructor { type_name, arity, .. } => {
-        format!("<constructor for `{}` arity {}>", type_name, arity)
-      },
-      Expr::Tuple(exprs) => paren_wrapped_vec(exprs.iter().map(|x| x.to_repl(symbol_table))),
-      _ => format!("{:?}", self),
-    }
-  }
-
-  fn replace_conditional_target_sigil(self, replacement: &Expr) -> Expr {
-    use self::Expr::*;
-
-    match self {
-      ConditionalTargetSigilValue => replacement.clone(),
-      Unit | Lit(_) | Func(_) | Sym(_) | Constructor { .. } |
-       CaseMatch { .. } | UnimplementedSigilValue | ReductionError(_) => self,
-      Tuple(exprs) => Tuple(exprs.into_iter().map(|e| e.replace_conditional_target_sigil(replacement)).collect()),
-      Call { f, args } => {
-        let new_args = args.into_iter().map(|e| e.replace_conditional_target_sigil(replacement)).collect();
-        Call { f, args: new_args }
-      },
-      Conditional { .. } => panic!("Dunno if I need this, but if so implement"),
-      Assign { .. } => panic!("I'm pretty sure I don't need this"),
-    }
-  }
-}
-
-impl<'a> State<'a> {
-  pub fn evaluate(&mut self, ast: ReducedAST, repl: bool) -> Vec<Result<String, String>> {
-    let mut acc = vec![];
-
-    // handle prebindings
-    for statement in ast.0.iter() {
-      self.prebinding(statement);
-    }
-
-    for statement in ast.0 {
-      match self.statement(statement) {
-        Ok(Some(ref output)) if repl => {
-          let ref symbol_table = self.symbol_table_handle.borrow();
-          acc.push(Ok(output.to_repl(symbol_table)))
-        },
-        Ok(_) => (),
-        Err(error) => {
-          acc.push(Err(format!("Runtime error: {}", error)));
-          return acc;
-        },
-      }
-    }
-    acc
-  }
-
-  fn prebinding(&mut self, stmt: &Stmt) {
-    match stmt {
-      Stmt::PreBinding { name, func } => {
-        let v_entry = ValueEntry::Binding { constant: true, val: Node::Expr(Expr::Func(func.clone())) };
-        self.values.insert(name.clone(), v_entry);
-      },
-      Stmt::Expr(_expr) => {
-        //TODO have this support things like nested function defs
-
-      },
-      _ => ()
-    }
-  }
-
-  fn statement(&mut self, stmt: Stmt) -> EvalResult<Option<Node>> {
-    match stmt {
-      Stmt::Binding { name, constant, expr } => {
-        let val = self.expression(Node::Expr(expr))?;
-        self.values.insert(name.clone(), ValueEntry::Binding { constant, val });
-        Ok(None)
-      },
-      Stmt::Expr(expr) => Ok(Some(self.expression(expr.to_node())?)),
-      Stmt::PreBinding {..} | Stmt::Noop => Ok(None),
-    }
-  }
-
-  fn block(&mut self, stmts: Vec<Stmt>) -> EvalResult<Node> {
-    let mut ret = None;
-    for stmt in stmts {
-      ret = self.statement(stmt)?;
-    }
-    Ok(ret.unwrap_or(Node::Expr(Expr::Unit)))
-  }
-
-  fn expression(&mut self, node: Node) -> EvalResult<Node> {
-    use self::Expr::*;
-    match node {
-      t @ Node::PrimTuple { .. } => Ok(t),
-      obj @ Node::PrimObject { .. } =>  Ok(obj),
-      Node::Expr(expr) => match expr {
-        literal @ Lit(_) => Ok(Node::Expr(literal)),
-        Call { box f, args } => self.call_expression(f, args),
-        Sym(v) => self.handle_sym(v),
-        Constructor { arity, ref name, tag, .. } if arity == 0 => Ok(Node::PrimObject { name: name.clone(), tag, items: vec![] }),
-        constructor @ Constructor { .. } => Ok(Node::Expr(constructor)),
-        func @ Func(_) => Ok(Node::Expr(func)),
-        Tuple(exprs) => {
-          let nodes = exprs.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
-          Ok(Node::PrimTuple { items: nodes })
-        },
-        Conditional { box cond, then_clause, else_clause } => self.conditional(cond, then_clause, else_clause),
-        Assign { box val, box expr } => self.assign_expression(val, expr),
-        Unit => Ok(Node::Expr(Unit)),
-        CaseMatch { box cond, alternatives } => self.case_match_expression(cond, alternatives),
-        ConditionalTargetSigilValue => Ok(Node::Expr(ConditionalTargetSigilValue)),
-        UnimplementedSigilValue => Err(format!("Sigil value eval not implemented")),
-        ReductionError(err) => Err(format!("Reduction error: {}", err)),
-      }
-    }
-  }
-
-  fn call_expression(&mut self, f: Expr, args: Vec<Expr>) -> EvalResult<Node> {
-    use self::Expr::*;
-    match self.expression(Node::Expr(f))? {
-      Node::Expr(Constructor { type_name, name, tag, arity }) => self.apply_data_constructor(type_name, name, tag, arity, args),
-      Node::Expr(Func(f)) => self.apply_function(f, args),
-      other => return Err(format!("Tried to call {:?} which is not a function or data constructor", other)),
-    }
-  }
-
-  fn apply_data_constructor(&mut self, _type_name: Rc<String>, name: Rc<String>, tag: usize, arity: usize, args: Vec<Expr>) -> EvalResult<Node> {
-    if arity != args.len() {
-      return Err(format!("Data constructor {} requires {} arg(s)", name, arity));
-    }
-
-    let evaled_args = args.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
-    //let evaled_args = vec![];
-    Ok(Node::PrimObject {
-      name: name.clone(),
-      items: evaled_args,
-      tag 
-    })
-  }
-
-  fn apply_function(&mut self, f: Func, args: Vec<Expr>) -> EvalResult<Node> {
-    match f {
-      Func::BuiltIn(builtin) => Ok(self.apply_builtin(builtin, args)?),
-      Func::UserDefined { params, body, name } => {
-
-        if params.len() != args.len() {
-          return Err(format!("calling a {}-argument function with {} args", params.len(), args.len()))
-        }
-        let mut func_state = State {
-          values: self.values.new_scope(name.map(|n| format!("{}", n))),
-          symbol_table_handle: self.symbol_table_handle.clone(),
-        };
-        for (param, val) in params.into_iter().zip(args.into_iter()) {
-          let val = func_state.expression(Node::Expr(val))?;
-          func_state.values.insert(param, ValueEntry::Binding { constant: true, val });
-        }
-        // TODO figure out function return semantics
-        func_state.block(body)
-      }
-    }
-  }
-
-  fn apply_builtin(&mut self, builtin: Builtin, args: Vec<Expr>) -> EvalResult<Node> {
-    use self::Expr::*;
-    use self::Lit::*;
-    use Builtin::*;
-
-    let evaled_args: Result<Vec<Node>, String> = args.into_iter().map(|arg| self.expression(arg.to_node()))
-      .collect();
-    let evaled_args = evaled_args?;
-
-    Ok(match (builtin, evaled_args.as_slice()) {
-      (FieldAccess, &[Node::PrimObject { .. }]) => {
-        //TODO implement field access
-        unimplemented!()
-      },
-      (binop, &[Node::Expr(ref lhs), Node::Expr(ref rhs)]) => match (binop, lhs, rhs) {
-        /* binops */
-        (Add, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l + r)),
-        (Concatenate, Lit(StringLit(ref s1)), Lit(StringLit(ref s2))) => Lit(StringLit(Rc::new(format!("{}{}", s1, s2)))),
-        (Subtract, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l - r)),
-        (Multiply, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l * r)),
-        (Divide, Lit(Nat(l)), Lit(Nat(r))) => Lit(Float((*l as f64)/ (*r as f64))),
-        (Quotient, Lit(Nat(l)), Lit(Nat(r))) => if *r == 0 {
-          return Err(format!("divide by zero"));
-        } else {
-          Lit(Nat(l / r))
-        },
-        (Modulo, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l % r)),
-        (Exponentiation, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l ^ r)),
-        (BitwiseAnd, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l & r)),
-        (BitwiseOr, Lit(Nat(l)), Lit(Nat(r))) => Lit(Nat(l | r)),
-
-        /* comparisons */
-        (Equality, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(Bool(l)), Lit(Bool(r))) => Lit(Bool(l == r)),
-        (Equality, Lit(StringLit(ref l)), Lit(StringLit(ref r))) => Lit(Bool(l == r)),
-
-        (LessThan, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l < r)),
-        (LessThan, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l < r)),
-        (LessThan, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l < r)),
-
-        (LessThanOrEqual, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l <= r)),
-        (LessThanOrEqual, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l <= r)),
-        (LessThanOrEqual, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l <= r)),
-
-        (GreaterThan, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l > r)),
-        (GreaterThan, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l > r)),
-        (GreaterThan, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l > r)),
-
-        (GreaterThanOrEqual, Lit(Nat(l)), Lit(Nat(r))) => Lit(Bool(l >= r)),
-        (GreaterThanOrEqual, Lit(Int(l)), Lit(Int(r))) => Lit(Bool(l >= r)),
-        (GreaterThanOrEqual, Lit(Float(l)), Lit(Float(r))) => Lit(Bool(l >= r)),
-        _ => return Err("No valid binop".to_string())
-      }.to_node(),
-      (prefix, &[Node::Expr(ref arg)]) => match (prefix, arg) {
-        (BooleanNot, Lit(Bool(true))) => Lit(Bool(false)),
-        (BooleanNot, Lit(Bool(false))) => Lit(Bool(true)),
-        (Negate, Lit(Nat(n))) => Lit(Int(-1*(*n as i64))),
-        (Negate, Lit(Int(n))) => Lit(Int(-1*(*n as i64))),
-        (Increment, Lit(Int(n))) => Lit(Int(*n)),
-        (Increment, Lit(Nat(n))) => Lit(Nat(*n)),
-        _ => return Err("No valid prefix op".to_string())
-      }.to_node(),
-
-      /* builtin functions */
-      (IOPrint, &[ref anything]) => {
-        let ref symbol_table = self.symbol_table_handle.borrow();
-        print!("{}", anything.to_repl(symbol_table));
-        Expr::Unit.to_node()
-      },
-      (IOPrintLn, &[ref anything]) => {
-        let ref symbol_table = self.symbol_table_handle.borrow();
-        println!("{}", anything.to_repl(symbol_table));
-        Expr::Unit.to_node()
-      },
-      (IOGetLine, &[]) => {
-        let mut buf = String::new();
-        io::stdin().read_line(&mut buf).expect("Error readling line in 'getline'");
-        Lit(StringLit(Rc::new(buf.trim().to_string()))).to_node()
-      },
-      (x, args) => return Err(format!("bad or unimplemented builtin {:?} | {:?}", x, args)),
-    })
-  }
-
-  fn conditional(&mut self, cond: Expr, then_clause: Vec<Stmt>, else_clause: Vec<Stmt>) -> EvalResult<Node> {
-    let cond = self.expression(Node::Expr(cond))?;
-    Ok(match cond {
-      Node::Expr(Expr::Lit(Lit::Bool(true))) =>  self.block(then_clause)?,
-      Node::Expr(Expr::Lit(Lit::Bool(false))) => self.block(else_clause)?,
-      _ => return Err(format!("Conditional with non-boolean condition"))
-    })
-  }
-
-  fn assign_expression(&mut self, val: Expr, expr: Expr) -> EvalResult<Node> {
-    let name = match val  {
-      Expr::Sym(name) => name,
-      _ => return Err(format!("Trying to assign to a non-value")),
-    };
-
-    let constant = match self.values.lookup(&name) {
-      None => return Err(format!("Constant {} is undefined", name)),
-      Some(ValueEntry::Binding { constant, .. }) => constant.clone(),
-    };
-    if constant {
-      return Err(format!("trying to update {}, a non-mutable binding", name));
-    }
-    let val = self.expression(Node::Expr(expr))?;
-    self.values.insert(name.clone(), ValueEntry::Binding { constant: false, val });
-    Ok(Node::Expr(Expr::Unit))
-  }
-
-  fn guard_passes(&mut self, guard: &Option<Expr>, cond: &Node) -> EvalResult<bool> {
-    if let Some(ref guard_expr) = guard {
-      let guard_expr = match cond {
-        Node::Expr(ref e) => guard_expr.clone().replace_conditional_target_sigil(e),
-        _ => guard_expr.clone()
-      };
-      Ok(self.expression(guard_expr.to_node())?.is_true())
-    } else {
-      Ok(true)
-    }
-  }
-
-  fn case_match_expression(&mut self, cond: Expr, alternatives: Vec<Alternative>) -> EvalResult<Node> {
-
-    //TODO need to handle recursive subpatterns
-    let all_subpatterns_pass = |state: &mut State, subpatterns: &Vec<Option<Subpattern>>, items: &Vec<Node>| -> EvalResult<bool> {
-
-      if subpatterns.len() == 0 {
-        return Ok(true)
-      }
-
-      if items.len() != subpatterns.len() {
-        return Err(format!("Subpattern length isn't correct items {} subpatterns {}", items.len(), subpatterns.len()));
-      }
-
-      for (maybe_subp, cond) in subpatterns.iter().zip(items.iter()) {
-        if let Some(subp) = maybe_subp {
-          if !state.guard_passes(&subp.guard, &cond)? {
-            return Ok(false)
-          }
-        }
-      }
-      Ok(true)
-    };
-
-    let cond = self.expression(Node::Expr(cond))?;
-    for alt in alternatives {
-      // no matter what type of condition we have, ignore alternative if the guard evaluates false
-      if !self.guard_passes(&alt.matchable.guard, &cond)? {
-        continue;
-      }
-
-      match cond {
-        Node::PrimObject { ref tag, ref items, .. } => {
-          if alt.matchable.tag.map(|t| t == *tag).unwrap_or(true) {
-            let mut inner_state = self.new_frame(items, &alt.matchable.bound_vars);
-            if all_subpatterns_pass(&mut inner_state, &alt.matchable.subpatterns, items)? {
-              return inner_state.block(alt.item);
-            } else {
-              continue;
-            }
-          }
-        },
-        Node::PrimTuple { ref items } =>  {
-          let mut inner_state = self.new_frame(items, &alt.matchable.bound_vars);
-          if all_subpatterns_pass(&mut inner_state, &alt.matchable.subpatterns, items)? {
-            return inner_state.block(alt.item);
-          } else {
-            continue;
-          }
-        },
-        Node::Expr(ref _e) => {
-          if let None = alt.matchable.tag {
-            return self.block(alt.item)
-          }
-        }
-      }
-    }
-    Err(format!("{:?} failed pattern match", cond))
-  }
-
-  //TODO if I don't need to lookup by name here...
-  fn handle_sym(&mut self, name: Rc<String>) -> EvalResult<Node> {
-    use self::ValueEntry::*;
-    use self::Func::*;
-    //TODO add a layer of indirection here to talk to the symbol table first, and only then look up
-    //in the values table
-
-    let symbol_table = self.symbol_table_handle.borrow();
-    let value = symbol_table.lookup_by_fqsn(&fqsn!(name ; tr));
-    Ok(match value {
-      Some(Symbol { name, spec, .. }) => match spec {
-        //TODO I'll need this type_name later to do a table lookup
-        SymbolSpec::DataConstructor { type_name: _type_name, type_args, .. } => {
-          if type_args.len() == 0 {
-            Node::PrimObject { name: name.clone(), tag: 0, items: vec![] }
-          } else {
-            return Err(format!("This data constructor thing not done"))
-          }
-        },
-        SymbolSpec::Func(_) => match self.values.lookup(&name) {
-          Some(Binding { val: Node::Expr(Expr::Func(UserDefined { name, params, body })), .. }) => {
-            Node::Expr(Expr::Func(UserDefined { name: name.clone(), params: params.clone(), body: body.clone() }))
-          },
-          _ => unreachable!(),
-        },
-        SymbolSpec::RecordConstructor { .. } => return Err(format!("This shouldn't be a record!")),
-        SymbolSpec::Binding => match self.values.lookup(&name) {
-          Some(Binding { val, .. }) => val.clone(),
-          None => return Err(format!("Symbol {} exists in symbol table but not in evaluator table", name))
-        }
-      },
-      //TODO ideally this should be returning a runtime error if this is ever None, but it's not
-      //handling all bindings correctly yet
-      //None => return Err(format!("Couldn't find value {}", name)),
-      None => match self.values.lookup(&name) {
-        Some(Binding { val, .. }) => val.clone(),
-        None => return Err(format!("Couldn't find value {}", name)),
-      }
-    })
-  }
-}

schala-lang/language/src/eval/test.rs

@@ -1,260 +0,0 @@
-#![cfg(test)]
-
-use std::cell::RefCell;
-use std::rc::Rc;
-
-use crate::symbol_table::SymbolTable;
-use crate::scope_resolution::ScopeResolver;
-use crate::reduced_ast::reduce;
-use crate::eval::State;
-
-fn evaluate_all_outputs(input: &str) -> Vec<Result<String, String>> {
-  let symbol_table = Rc::new(RefCell::new(SymbolTable::new()));
-  let mut state = State::new(symbol_table);
-  let mut ast = crate::util::quick_ast(input);
-  state.symbol_table_handle.borrow_mut().add_top_level_symbols(&ast).unwrap();
-  {
-  let mut t = &mut state.symbol_table_handle.borrow_mut();
-  let mut scope_resolver = crate::scope_resolution::ScopeResolver::new(&mut t);
-  let _ = scope_resolver.resolve(&mut ast);
-  }
-
-  let reduced = reduce(&ast, &state.symbol_table_handle.borrow());
-  let all_output = state.evaluate(reduced, true);
-  all_output
-}
-
-macro_rules! test_in_fresh_env {
-  ($string:expr, $correct:expr) => {
-    {
-      let all_output = evaluate_all_outputs($string);
-      let ref output = all_output.last().unwrap();
-      assert_eq!(**output, Ok($correct.to_string()));
-    }
-  }
-}
-
-#[test]
-fn test_basic_eval() {
-  test_in_fresh_env!("1 + 2", "3");
-  test_in_fresh_env!("let mut a = 1; a = 2", "Unit");
-  /*
-     test_in_fresh_env!("let mut a = 1; a = 2; a", "2");
-     test_in_fresh_env!(r#"("a", 1 + 2)"#, r#"("a", 3)"#);
-     */
-}
-
-#[test]
-fn op_eval() {
-  test_in_fresh_env!("- 13", "-13");
-  test_in_fresh_env!("10 - 2", "8");
-}
-
-#[test]
-fn function_eval() {
-  test_in_fresh_env!("fn oi(x) { x + 1 }; oi(4)", "5");
-  test_in_fresh_env!("fn oi(x) { x + 1 }; oi(1+2)", "4");
-}
-
-#[test]
-fn scopes() {
-  let scope_ok = r#"
-    let a = 20
-    fn haha() {
-      let a = 10
-      a
-    }
-    haha()
-    "#;
-    test_in_fresh_env!(scope_ok, "10");
-    let scope_ok = r#"
-    let a = 20
-    fn haha() {
-      let a = 10
-      a
-    }
-    a
-    "#;
-    test_in_fresh_env!(scope_ok, "20");
-}
-
-#[test]
-fn if_is_patterns() {
-  let source = r#"
-type Option<T> = Some(T) | None
-let x = Option::Some(9); if x is Option::Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "9");
-
-  let source = r#"
-type Option<T> = Some(T) | None
-let x = Option::None; if x is Option::Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "0");
-}
-
-#[test]
-fn full_if_matching() {
-  let source = r#"
-type Option<T> = Some(T) | None
-let a = Option::None
-if a { is Option::None -> 4, is Option::Some(x) -> x }
-"#;
-test_in_fresh_env!(source, "4");
-
-let source = r#"
-type Option<T> = Some(T) | None
-let a = Option::Some(99)
-if a { is Option::None -> 4, is Option::Some(x) -> x }
-"#;
-test_in_fresh_env!(source, "99");
-
-let source = r#"
-let a = 10
-if a { is 10 -> "x", is 4 -> "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-
-let source = r#"
-let a = 10
-if a { is 15 -> "x", is 10 -> "y" }
-"#;
-test_in_fresh_env!(source, "\"y\"");
-}
-
-#[test]
-fn string_pattern() {
-  let source = r#"
-let a = "foo"
-if a { is "foo" -> "x", is _ -> "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern() {
-  let source = r#"
-let a = true
-if a { 
-  is true -> "x",
-  is false -> "y"
-}
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern_2() {
-  let source = r#"
-let a = false
-if a { is true -> "x", is false -> "y" }
-"#;
-test_in_fresh_env!(source, "\"y\"");
-}
-
-#[test]
-fn ignore_pattern() {
-  let source = r#"
-type Option<T> = Some(T) | None
-if Option::Some(10) {
-  is _ -> "hella"
-}
-"#;
-test_in_fresh_env!(source, "\"hella\"");
-}
-
-#[test]
-fn tuple_pattern() {
-  let source = r#"
-if (1, 2) {
-  is (1, x) -> x,
-  is _ -> 99
-}
-"#;
-test_in_fresh_env!(source, 2);
-}
-
-
-#[test]
-fn tuple_pattern_2() {
-  let source = r#"
-if (1, 2) {
-  is (10, x) -> x,
-  is (y, x) -> x + y
-}
-"#;
-test_in_fresh_env!(source, 3);
-}
-
-#[test]
-fn tuple_pattern_3() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) -> x,
-  is (1, x) -> x
-}
-"#;
-test_in_fresh_env!(source, 5);
-}
-
-#[test]
-fn tuple_pattern_4() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) -> x,
-  is (1, x) -> x,
-}
-"#;
-test_in_fresh_env!(source, 5);
-}
-
-#[test]
-fn  prim_obj_pattern() {
-  let source = r#"
-type Stuff = Mulch(Nat) | Jugs(Nat, String) | Mardok
-let a = Stuff::Mulch(20)
-let b = Stuff::Jugs(1, "haha")
-let c = Stuff::Mardok
-
-let x = if a {
-  is Stuff::Mulch(20) -> "x",
-  is _ -> "ERR"
-}
-
-let y = if b {
-  is Stuff::Mulch(n) -> "ERR",
-  is Stuff::Jugs(2, _) -> "ERR",
-  is Stuff::Jugs(1, s) -> s,
-  is _ -> "ERR",
-}
-
-let z = if c {
-  is Stuff::Jugs(_, _) -> "ERR",
-  is Stuff::Mardok -> "NIGH",
-  is _ -> "ERR",
-}
-
-(x, y, z)
-"#;
-test_in_fresh_env!(source, r#"("x", "haha", "NIGH")"#);
-}
-
-#[test]
-fn basic_lambda_syntax() {
-  let source = r#"
-let q = \(x, y) { x * y }
-let x = q(5,2)
-let y = \(m, n, o) { m + n + o }(1,2,3)
-(x, y)
-  "#;
-test_in_fresh_env!(source, r"(10, 6)");
-}
-
-#[test]
-fn lambda_syntax_2() {
-  let source = r#"
-fn milta() {
-  \(x) { x + 33 }
-}
-milta()(10)
-  "#;
-  test_in_fresh_env!(source, "43");
-  }

schala-lang/language/src/lib.rs

@@ -1,44 +0,0 @@
-#![feature(trace_macros)]
-#![feature(custom_attribute)]
-//#![feature(unrestricted_attribute_tokens)]
-#![feature(slice_patterns, box_patterns, box_syntax)]
-
-//! `schala-lang` is where the Schala programming language is actually implemented. 
-//! It defines the `Schala` type, which contains the state for a Schala REPL, and implements
-//! `ProgrammingLanguageInterface` and the chain of compiler passes for it.
-
-extern crate itertools;
-#[macro_use]
-extern crate lazy_static;
-#[macro_use]
-extern crate maplit;
-extern crate schala_repl;
-#[macro_use]
-extern crate schala_lang_codegen;
-extern crate ena;
-extern crate derivative;
-
-
-macro_rules! bx {
-  ($e:expr) => { Box::new($e) }
-}
-
-#[macro_use]
-mod util;
-#[macro_use]
-mod typechecking;
-mod debugging;
-
-mod tokenizing;
-mod ast;
-mod parsing;
-#[macro_use]
-mod symbol_table;
-mod scope_resolution;
-mod builtin;
-mod reduced_ast;
-mod eval;
-
-mod schala;
-
-pub use schala::Schala;

schala-lang/language/src/parsing/test.rs

@@ -1,709 +0,0 @@
-#![cfg(test)]
-use ::std::rc::Rc;
-use std::str::FromStr;
-
-use super::tokenize;
-use super::ParseResult;
-use crate::ast::{ItemIdStore, AST, Meta, Expression, Statement, StatementKind, IfExpressionBody, Discriminator, Pattern, PatternLiteral, TypeBody, Enumerator, ForBody, InvocationArgument, FormalParam, PrefixOp, BinOp, QualifiedName};
-use super::Declaration::*;
-use super::Signature;
-use super::TypeIdentifier::*;
-use super::TypeSingletonName;
-use super::ExpressionKind::*;
-use super::Variant::*;
-use super::ForBody::*;
-
-fn parse(input: &str) -> ParseResult<AST> {
-  let tokens: Vec<crate::tokenizing::Token> = tokenize(input);
-  let mut parser = super::Parser::new(tokens);
-  parser.parse()
-}
-
-macro_rules! parse_test {
-  ($string:expr, $correct:expr) => {
-    assert_eq!(parse($string).unwrap(), $correct)
-  };
-}
-macro_rules! parse_test_wrap_ast {
-  ($string:expr, $correct:expr) => { parse_test!($string, AST { id: ItemIdStore::new_id(), statements: vec![$correct] }) }
-}
-macro_rules! parse_error {
-  ($string:expr) => { assert!(parse($string).is_err()) }
-}
-macro_rules! qname {
-  (  $( $component:expr),* ) => {
-    {
-    let mut components = vec![];
-    $(
-      components.push(rc!($component));
-    )*
-    QualifiedName { components, id: ItemIdStore::new_id() }
-    }
-  };
-}
-macro_rules! val {
-  ($var:expr) => { Value(QualifiedName { components: vec![Rc::new($var.to_string())], id: ItemIdStore::new_id() }) };
-}
-macro_rules! ty {
-  ($name:expr) => { Singleton(tys!($name)) }
-}
-macro_rules! tys {
-  ($name:expr) => { TypeSingletonName { name: Rc::new($name.to_string()), params: vec![] } };
-}
-
-macro_rules! decl {
-  ($expr_type:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Declaration($expr_type) }
-  };
-}
-
-macro_rules! ex {
-  ($expr_type:expr) => { Expression::new(ItemIdStore::new_id(), $expr_type) };
-  (m $expr_type:expr) => { Meta::new(Expression::new(ItemIdStore::new_id(), $expr_type)) };
-  (m $expr_type:expr, $type_anno:expr) => { Meta::new(Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno)) };
-  (s $expr_text:expr) => {
-    {
-      let tokens: Vec<crate::tokenizing::Token> = tokenize($expr_text);
-      let mut parser = super::Parser::new(tokens);
-      parser.expression().unwrap()
-    }
-  };
-}
-
-macro_rules! inv {
-  ($expr_type:expr) => { InvocationArgument::Positional($expr_type) }
-}
-
-macro_rules! binexp {
-  ($op:expr, $lhs:expr, $rhs:expr) => { BinExp(BinOp::from_sigil($op), bx!(Expression::new(ItemIdStore::new_id(), $lhs).into()), bx!(Expression::new(ItemIdStore::new_id(), $rhs).into())) }
-}
-macro_rules! prefexp {
-  ($op:expr, $lhs:expr) => { PrefixExp(PrefixOp::from_str($op).unwrap(), bx!(Expression::new(ItemIdStore::new_id(), $lhs).into())) }
-}
-macro_rules! exst {
-  ($expr_type:expr) => { Meta::new(Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::new(ItemIdStore::new_id(), $expr_type).into())}) };
-  ($expr_type:expr, $type_anno:expr) => { Meta::new(Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno).into())}) };
-  ($op:expr, $lhs:expr, $rhs:expr) => { Meta::new(
-    Statement { id: ItemIdStore::new_id(), ,kind: StatementKind::Expression(ex!(binexp!($op, $lhs, $rhs)))}
-  )};
-  (s $statement_text:expr) => {
-    {
-      let tokens: Vec<crate::tokenizing::Token> = tokenize($statement_text);
-      let mut parser = super::Parser::new(tokens);
-      Meta::new(parser.statement().unwrap())
-    }
-  }
-}
-
-#[test]
-fn parsing_number_literals_and_binexps() {
-  parse_test_wrap_ast! { ".2", exst!(FloatLiteral(0.2)) };
-  parse_test_wrap_ast! { "8.1", exst!(FloatLiteral(8.1)) };
-
-  parse_test_wrap_ast! { "0b010", exst!(NatLiteral(2)) };
-  parse_test_wrap_ast! { "0b0_1_0_", exst!(NatLiteral(2)) }
-
-  parse_test_wrap_ast! {"0xff", exst!(NatLiteral(255)) };
-  parse_test_wrap_ast! {"0xf_f_", exst!(NatLiteral(255)) };
-
-  parse_test_wrap_ast! {"0xf_f_+1", exst!(binexp!("+", NatLiteral(255), NatLiteral(1))) };
-
-  parse_test! {"3; 4; 4.3",
-    AST {
-      id: ItemIdStore::new_id(),
-      statements: vec![exst!(NatLiteral(3)), exst!(NatLiteral(4)),
-      exst!(FloatLiteral(4.3))]
-    }
-  };
-
-  parse_test_wrap_ast!("1 + 2 * 3",
-    exst!(binexp!("+", NatLiteral(1), binexp!("*", NatLiteral(2), NatLiteral(3))))
-  );
-
-  parse_test_wrap_ast!("1 * 2 + 3",
-    exst!(binexp!("+", binexp!("*", NatLiteral(1), NatLiteral(2)), NatLiteral(3)))
-    ) ;
-
-  parse_test_wrap_ast!("1 && 2", exst!(binexp!("&&", NatLiteral(1), NatLiteral(2))));
-
-  parse_test_wrap_ast!("1 + 2 * 3 + 4", exst!(
-    binexp!("+",
-      binexp!("+", NatLiteral(1), binexp!("*", NatLiteral(2), NatLiteral(3))),
-      NatLiteral(4))));
-
-  parse_test_wrap_ast!("(1 + 2) * 3",
-    exst!(binexp!("*", binexp!("+", NatLiteral(1), NatLiteral(2)), NatLiteral(3))));
-
-  parse_test_wrap_ast!(".1 + .2", exst!(binexp!("+", FloatLiteral(0.1), FloatLiteral(0.2))));
-  parse_test_wrap_ast!("1 / 2", exst!(binexp!("/", NatLiteral(1), NatLiteral(2))));
-}
-
-#[test]
-fn parsing_tuples() {
-  parse_test_wrap_ast!("()", exst!(TupleLiteral(vec![])));
-  parse_test_wrap_ast!("(\"hella\", 34)", exst!(
-    TupleLiteral(
-      vec![ex!(s r#""hella""#).into(), ex!(s "34").into()]
-    )
-  ));
-  parse_test_wrap_ast!("((1+2), \"slough\")", exst!(TupleLiteral(vec![
-    ex!(binexp!("+", NatLiteral(1), NatLiteral(2))).into(),
-    ex!(StringLiteral(rc!(slough))).into(),
-  ])))
-}
-
-#[test]
-fn parsing_identifiers() {
-  parse_test_wrap_ast!("a", exst!(val!("a")));
-  parse_test_wrap_ast!("some_value", exst!(val!("some_value")));
-  parse_test_wrap_ast!("a + b", exst!(binexp!("+", val!("a"), val!("b"))));
-  //parse_test!("a[b]", AST(vec![Expression(
-  //parse_test!("a[]", <- TODO THIS NEEDS TO FAIL
-  //parse_test("a()[b]()[d]")
-  //TODO fix this parsing stuff
-  /*
-  parse_test! { "perspicacity()[a]", AST(vec![
-    exst!(Index {
-      indexee: bx!(ex!(Call { f: bx!(ex!(val!("perspicacity"))), arguments: vec![] })),
-      indexers: vec![ex!(val!("a"))]
-    })
-  ])
-  }
-  */
-  parse_test_wrap_ast!("a[b,c]", exst!(Index { indexee: bx!(ex!(m val!("a"))), indexers: vec![ex!(m val!("b")), ex!(m val!("c"))]} ));
-
-  parse_test_wrap_ast!("None", exst!(val!("None")));
-  parse_test_wrap_ast!("Pandas {  a: x + y }",
-    exst!(NamedStruct { name: Meta::new(qname!(Pandas)), fields: vec![(rc!(a), ex!(m binexp!("+", val!("x"), val!("y"))))]})
-  );
-  parse_test_wrap_ast! { "Pandas { a: n, b: q, }",
-    exst!(NamedStruct { name: Meta::new(qname!(Pandas)), fields:
-    vec![(rc!(a), ex!(m val!("n"))), (rc!(b), ex!(m val!("q")))]
-    }
-    )
-  };
-}
-
-
-#[test]
-fn qualified_identifiers() {
-  parse_test_wrap_ast! {
-    "let q_q = Yolo::Swaggins",
-    Meta::new(decl!(Binding { name: rc!(q_q), constant: true, type_anno: None,
-      expr: Meta::new(Expression::new(ItemIdStore::new_id(), Value(qname!(Yolo, Swaggins)))),
-    }))
-  }
-
-  parse_test_wrap_ast! {
-    "thing::item::call()",
-    exst!(Call { f: bx![ex!(m Value(qname!(thing, item, call)))], arguments: vec![] })
-  }
-}
-
-#[test]
-fn reserved_words() {
-  parse_error!("module::item::call()");
-}
-
-#[test]
-fn parsing_complicated_operators() {
-  parse_test_wrap_ast!("a <- b", exst!(binexp!("<-", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a || b", exst!(binexp!("||", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a<>b", exst!(binexp!("<>", val!("a"), val!("b"))));
-  parse_test_wrap_ast!("a.b.c.d", exst!(binexp!(".",
-                                              binexp!(".",
-                                                binexp!(".", val!("a"), val!("b")),
-                                              val!("c")),
-                                              val!("d"))));
-  parse_test_wrap_ast!("-3", exst!(prefexp!("-", NatLiteral(3))));
-  parse_test_wrap_ast!("-0.2", exst!(prefexp!("-", FloatLiteral(0.2))));
-  parse_test_wrap_ast!("!3", exst!(prefexp!("!", NatLiteral(3))));
-  parse_test_wrap_ast!("a <- -b", exst!(binexp!("<-", val!("a"), prefexp!("-", val!("b")))));
-  parse_test_wrap_ast!("a <--b", exst!(binexp!("<--", val!("a"), val!("b"))));
-}
-
-#[test]
-fn parsing_functions() {
-  parse_test_wrap_ast!("fn oi()",  Meta::new(decl!(FuncSig(Signature { name: rc!(oi), operator: false, params: vec![], type_anno: None }))));
-  parse_test_wrap_ast!("oi()", exst!(Call { f: bx!(ex!(m val!("oi"))), arguments: vec![] }));
-  parse_test_wrap_ast!("oi(a, 2 + 2)", exst!(Call
-  { f: bx!(ex!(m val!("oi"))),
-    arguments: vec![inv!(ex!(m val!("a"))), inv!(ex!(m binexp!("+", NatLiteral(2), NatLiteral(2)))).into()]
-  }));
-  parse_error!("a(b,,c)");
-
-  parse_test_wrap_ast!("fn a(b, c: Int): Int", Meta::new(decl!(
-    FuncSig(Signature { name: rc!(a), operator: false, params: vec![
-      FormalParam { name: rc!(b), anno: None, default: None },
-      FormalParam { name: rc!(c), anno: Some(ty!("Int")), default: None }
-    ], type_anno: Some(ty!("Int")) }))));
-
-
-  parse_test_wrap_ast!("fn a(x) { x() }", Meta::new(decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), anno: None, default: None }], type_anno: None },
-      vec![exst!(Call { f: bx!(ex!(m val!("x"))), arguments: vec![] })]))));
-  parse_test_wrap_ast!("fn a(x) {\n x() }", Meta::new(decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), anno: None, default: None }], type_anno: None },
-      vec![exst!(Call { f: bx!(ex!(m val!("x"))), arguments: vec![] })]))));
-
-  let multiline = r#"
-fn a(x) {
-x()
-}
-"#;
-  parse_test_wrap_ast!(multiline, Meta::new(decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), default: None, anno: None }], type_anno: None },
-      vec![exst!(Call { f: bx!(ex!(m val!("x"))), arguments: vec![] })]))));
-  let multiline2 = r#"
-fn a(x) {
-
-x()
-
-}
-"#;
-  parse_test_wrap_ast!(multiline2, Meta::new(decl!(
-    FuncDecl(Signature { name: rc!(a), operator: false, params: vec![FormalParam { name: rc!(x), default: None, anno: None }], type_anno: None },
-      vec![exst!(s "x()")]))));
-}
-
-#[test]
-fn functions_with_default_args() {
-  parse_test_wrap_ast! {
-    "fn func(x: Int, y: Int = 4) { }",
-    Meta::new(decl!(
-      FuncDecl(Signature { name: rc!(func), operator: false, type_anno: None, params: vec![
-        FormalParam { name: rc!(x), default: None, anno: Some(ty!("Int")) },
-        FormalParam { name: rc!(y), default: Some(Meta::new(ex!(s "4"))), anno: Some(ty!("Int")) }
-      ]}, vec![])
-    ))
-  };
-}
-
-#[test]
-fn parsing_bools() {
-  parse_test_wrap_ast!("false", exst!(BoolLiteral(false)));
-  parse_test_wrap_ast!("true", exst!(BoolLiteral(true)));
-}
-
-#[test]
-fn parsing_strings() {
-  parse_test_wrap_ast!(r#""hello""#, exst!(StringLiteral(rc!(hello))));
-}
-
-#[test]
-fn parsing_types() {
-  parse_test_wrap_ast!("type Yolo = Yolo", Meta::new(decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: false} )));
-  parse_test_wrap_ast!("type mut Yolo = Yolo", Meta::new(decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: true} )));
-  parse_test_wrap_ast!("type alias Sex = Drugs", Meta::new(decl!(TypeAlias(rc!(Sex), rc!(Drugs)))));
-  parse_test_wrap_ast!("type Sanchez = Miguel | Alejandro(Int, Option<a>) | Esperanza { a: Int, b: String }",
-  Meta::new(decl!(TypeDecl {
-    name: tys!("Sanchez"),
-    body: TypeBody(vec![
-      UnitStruct(rc!(Miguel)),
-      TupleStruct(rc!(Alejandro), vec![
-        Singleton(TypeSingletonName { name: rc!(Int), params: vec![] }),
-        Singleton(TypeSingletonName { name: rc!(Option), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] }),
-      ]),
-      Record{
-        name: rc!(Esperanza),
-        members: vec![
-          (rc!(a), Singleton(TypeSingletonName { name: rc!(Int), params: vec![] })),
-          (rc!(b), Singleton(TypeSingletonName { name: rc!(String), params: vec![] })),
-        ]
-      }
-    ]),
-    mutable: false
-   })));
-
-  parse_test_wrap_ast! {
-    "type Jorge<a> = Diego | Kike(a)",
-    Meta::new(decl!(TypeDecl{
-      name: TypeSingletonName { name: rc!(Jorge), params: vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })] },
-      body: TypeBody(vec![UnitStruct(rc!(Diego)), TupleStruct(rc!(Kike), vec![Singleton(TypeSingletonName { name: rc!(a), params: vec![] })])]),
-      mutable: false
-    }
-  ))
-  };
-}
-
-#[test]
-fn parsing_bindings() {
-  parse_test_wrap_ast!("let mut a = 10", Meta::new(decl!(Binding { name: rc!(a), constant: false, type_anno: None, expr: ex!(m NatLiteral(10)) } )));
-  parse_test_wrap_ast!("let a = 2 + 2", Meta::new(decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr: ex!(m binexp!("+", NatLiteral(2), NatLiteral(2))) }) ));
-  parse_test_wrap_ast!("let a: Nat = 2 + 2", Meta::new(decl!(
-    Binding { name: rc!(a), constant: true, type_anno: Some(Singleton(TypeSingletonName { name: rc!(Nat), params: vec![] })),
-    expr: Meta::new(ex!(binexp!("+", NatLiteral(2), NatLiteral(2)))) }
-  )));
-}
-
-#[test]
-fn parsing_block_expressions() {
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() }", exst!(
-      IfExpression {
-        discriminator: bx! {
-          Discriminator::Simple(ex!(m Call { f: bx!(ex!(m val!("a"))), arguments: vec![]}))
-        },
-        body: bx! {
-          IfExpressionBody::SimpleConditional(
-            vec![exst!(Call { f: bx!(ex!(m val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(m val!("c"))), arguments: vec![] })],
-            None
-          )
-        }
-      }
-    )
-  };
-
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() } else { q }", exst!(
-      IfExpression {
-        discriminator: bx! {
-          Discriminator::Simple(ex!(m Call { f: bx!(ex!(m val!("a"))), arguments: vec![]}))
-        },
-        body: bx! {
-          IfExpressionBody::SimpleConditional(
-            vec![exst!(Call { f: bx!(ex!(m val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(m val!("c"))), arguments: vec![] })],
-            Some(
-              vec![exst!(val!("q"))],
-            )
-          )
-        }
-      }
-    )
-  };
-
-  /*
-  parse_test!("if a() then { b(); c() }", AST(vec![exst!(
-      IfExpression(bx!(ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})),
-        vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-        None)
-      )]));
-  parse_test!(r#"
-  if true then {
-    const a = 10
-    b
-  } else {
-    c
-  }"#,
-  AST(vec![exst!(IfExpression(bx!(ex!(BoolLiteral(true))),
-    vec![decl!(Binding { name: rc!(a), constant: true, expr: ex!(NatLiteral(10)) }),
-          exst!(val!(rc!(b)))],
-    Some(vec![exst!(val!(rc!(c)))])))])
-  );
-
-  parse_test!("if a { b } else { c }", AST(vec![exst!(
-        IfExpression(bx!(ex!(val!("a"))),
-          vec![exst!(val!("b"))],
-          Some(vec![exst!(val!("c"))])))]));
-
-  parse_test!("if (A {a: 1}) { b } else { c }", AST(vec![exst!(
-        IfExpression(bx!(ex!(NamedStruct { name: rc!(A), fields: vec![(rc!(a), ex!(NatLiteral(1)))]})),
-          vec![exst!(val!("b"))],
-          Some(vec![exst!(val!("c"))])))]));
-
-  parse_error!("if A {a: 1} { b } else { c }");
-  */
-}
-#[test]
-fn parsing_interfaces() {
-  parse_test_wrap_ast!("interface Unglueable { fn unglue(a: Glue); fn mar(): Glue }",
-    Meta::new(decl!(Interface {
-      name: rc!(Unglueable),
-      signatures: vec![
-        Signature {
-          name: rc!(unglue),
-          operator: false,
-          params: vec![
-            FormalParam { name: rc!(a), anno: Some(Singleton(TypeSingletonName { name: rc!(Glue), params: vec![] })), default: None }
-          ],
-          type_anno: None
-        },
-        Signature { name: rc!(mar), operator: false, params: vec![], type_anno: Some(Singleton(TypeSingletonName { name: rc!(Glue), params: vec![] })) },
-      ]
-    }))
-  );
-}
-
-#[test]
-fn parsing_impls() {
-  parse_test_wrap_ast!("impl Heh { fn yolo(); fn swagg(); }",
-    Meta::new(
-    decl!(Impl {
-      type_name: ty!("Heh"),
-      interface_name: None,
-      block: vec![
-        FuncSig(Signature { name: rc!(yolo), operator: false, params: vec![], type_anno: None }),
-        FuncSig(Signature { name: rc!(swagg), operator: false, params: vec![], type_anno: None })
-      ] })));
-
-  parse_test_wrap_ast!("impl Mondai for Lollerino { fn yolo(); fn swagg(); }",
-    Meta::new(decl!(Impl {
-      type_name: ty!("Lollerino"),
-      interface_name: Some(TypeSingletonName { name: rc!(Mondai), params: vec![] }),
-      block: vec![
-        FuncSig(Signature { name: rc!(yolo), operator: false, params: vec![], type_anno: None}),
-        FuncSig(Signature { name: rc!(swagg), operator: false, params: vec![], type_anno: None })
-      ] })));
-
-  parse_test_wrap_ast!("impl Hella<T> for (Alpha, Omega) { }",
-    Meta::new(decl!(Impl {
-      type_name: Tuple(vec![ty!("Alpha"), ty!("Omega")]),
-      interface_name: Some(TypeSingletonName { name: rc!(Hella), params: vec![ty!("T")] }),
-      block: vec![]
-    }))
-  );
-
-  parse_test_wrap_ast!("impl Option<WTFMate> { fn oi() }",
-    Meta::new(
-    decl!(Impl {
-      type_name: Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("WTFMate")]}),
-      interface_name: None,
-      block: vec![
-        FuncSig(Signature { name: rc!(oi), operator: false, params: vec![], type_anno: None }),
-      ]
-    })));
-}
-
-#[test]
-fn parsing_type_annotations() {
-  parse_test_wrap_ast!("let a = b : Int",
-    Meta::new(
-    decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr:
-      ex!(m val!("b"), ty!("Int")) })));
-
-  parse_test_wrap_ast!("a : Int",
-    exst!(val!("a"), ty!("Int"))
-  );
-
-  parse_test_wrap_ast!("a : Option<Int>",
-    exst!(val!("a"), Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("Int")] }))
-  );
-
-  parse_test_wrap_ast!("a : KoreanBBQSpecifier<Kimchi, Option<Bulgogi> >",
-    exst!(val!("a"), Singleton(TypeSingletonName { name: rc!(KoreanBBQSpecifier), params: vec![
-      ty!("Kimchi"), Singleton(TypeSingletonName { name: rc!(Option), params: vec![ty!("Bulgogi")] })
-    ] }))
-  );
-
-  parse_test_wrap_ast!("a : (Int, Yolo<a>)",
-    exst!(val!("a"), Tuple(
-      vec![ty!("Int"), Singleton(TypeSingletonName {
-        name: rc!(Yolo), params: vec![ty!("a")]
-      })])));
-}
-
-#[test]
-fn parsing_lambdas() {
-  parse_test_wrap_ast! { r#"\(x) { x + 1}"#, exst!(
-      Lambda { params: vec![FormalParam { name: rc!(x), anno: None, default: None } ], type_anno: None, body: vec![exst!(s "x + 1")] }
-    )
-  }
-
-  parse_test_wrap_ast!(r#"\  (x: Int, y) { a;b;c;}"#,
-    exst!(Lambda {
-      params: vec![
-        FormalParam { name: rc!(x), anno: Some(ty!("Int")), default: None },
-        FormalParam { name: rc!(y), anno: None, default: None }
-      ],
-      type_anno: None,
-      body: vec![exst!(s "a"), exst!(s "b"), exst!(s "c")]
-    })
-  );
-
-  parse_test_wrap_ast! { r#"\(x){y}(1)"#,
-    exst!(Call { f: bx!(ex!(m
-      Lambda {
-        params: vec![
-          FormalParam { name: rc!(x), anno: None, default: None }
-        ],
-        type_anno: None,
-        body: vec![exst!(s "y")] }
-      )),
-      arguments: vec![inv!(ex!(m NatLiteral(1))).into()] })
-  };
-
-  parse_test_wrap_ast! {
-    r#"\(x: Int): String { "q" }"#,
-    exst!(Lambda {
-      params: vec![
-        FormalParam { name: rc!(x), anno: Some(ty!("Int")), default: None },
-      ],
-      type_anno: Some(ty!("String")),
-      body: vec![exst!(s r#""q""#)]
-    })
-  }
-}
-
-#[test]
-fn single_param_lambda() {
-  parse_test_wrap_ast! {
-    r"\x { x + 10 }",
-    exst!(Lambda {
-      params: vec![FormalParam { name: rc!(x), anno: None, default: None }],
-      type_anno: None,
-      body: vec![exst!(s r"x + 10")]
-    })
-  }
-
-  parse_test_wrap_ast! {
-    r"\x: Nat { x + 10 }",
-    exst!(Lambda {
-      params: vec![FormalParam { name: rc!(x), anno: Some(ty!("Nat")), default: None }],
-      type_anno: None,
-      body: vec![exst!(s r"x + 10")]
-    })
-  }
-}
-
-#[test]
-fn more_advanced_lambdas() {
-  parse_test! {
-    r#"fn wahoo() { let a = 10; \(x) { x + a } };
-    wahoo()(3) "#,
-    AST {
-      id: ItemIdStore::new_id(),
-      statements: vec![
-        exst!(s r"fn wahoo() { let a = 10; \(x) { x + a } }"),
-        exst! {
-        Call {
-          f: bx!(ex!(m Call { f: bx!(ex!(m val!("wahoo"))), arguments: vec![] })),
-          arguments: vec![inv!(ex!(m NatLiteral(3))).into()],
-        }
-      }
-    ]
-  }
-  }
-}
-
-#[test]
-  fn list_literals() {
-    parse_test_wrap_ast! {
-      "[1,2]",
-        exst!(ListLiteral(vec![ex!(m NatLiteral(1)), ex!(m NatLiteral(2))]))
-    };
-  }
-
-#[test]
-fn while_expr() {
-  parse_test_wrap_ast! {
-    "while { }",
-    exst!(WhileExpression { condition: None, body: vec![] })
-  }
-
-  parse_test_wrap_ast! {
-    "while a == b { }",
-    exst!(WhileExpression { condition: Some(bx![ex![m binexp!("==", val!("a"), val!("b"))]]), body: vec![] })
-  }
-}
-
-#[test]
-fn for_expr() {
-  parse_test_wrap_ast! {
-    "for { a <- maybeValue } return 1",
-    exst!(ForExpression {
-      enumerators: vec![Enumerator { id: rc!(a), generator: ex!(val!("maybeValue")) }],
-      body: bx!(MonadicReturn(ex!(s "1")))
-    })
-  }
-
-  parse_test_wrap_ast! {
-    "for n <- someRange { f(n); }",
-    exst!(ForExpression { enumerators: vec![Enumerator { id: rc!(n), generator: ex!(val!("someRange"))}],
-      body: bx!(ForBody::StatementBlock(vec![exst!(s "f(n)")]))
-    })
-  }
-}
-
-#[test]
-fn patterns() {
-  parse_test_wrap_ast! {
-    "if x is Some(a) then { 4 } else { 9 }", exst!(
-      IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(Pattern::TupleStruct(qname!(Some),
-            vec![Pattern::VarOrName(qname!(a))]), vec![exst!(s "4")], Some(vec![exst!(s "9")]))) }
-      )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Some(a) then 4 else 9", exst!(
-      IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(Pattern::TupleStruct(qname!(Some),
-              vec![Pattern::VarOrName(qname!(a))]), vec![exst!(s "4")], Some(vec![exst!(s "9")]))) }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Something { a, b: x } then { 4 } else { 9 }", exst!(
-      IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(
-            Pattern::Record(qname!(Something), vec![
-              (rc!(a),Pattern::Literal(PatternLiteral::StringPattern(rc!(a)))),
-              (rc!(b),Pattern::VarOrName(qname!(x)))
-            ]),
-            vec![exst!(s "4")], Some(vec![exst!(s "9")])))
-      }
-    )
-  }
-}
-
-#[test]
-fn pattern_literals() {
-  parse_test_wrap_ast! {
-    "if x is -1 then 1 else 2",
-    exst!(
-      IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(
-          Pattern::Literal(PatternLiteral::NumPattern { neg: true, num: NatLiteral(1) }),
-          vec![exst!(NatLiteral(1))],
-          Some(vec![exst!(NatLiteral(2))]),
-        ))
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is 1 then 1 else 2", 
-    exst!(
-      IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(
-            Pattern::Literal(PatternLiteral::NumPattern { neg: false, num: NatLiteral(1) }),
-            vec![exst!(s "1")],
-            Some(vec![exst!(s "2")]),
-            ))
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is true then 1 else 2", 
-    exst!(
-    IfExpression {
-        discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-        body: bx!(IfExpressionBody::SimplePatternMatch(
-        Pattern::Literal(PatternLiteral::BoolPattern(true)),
-        vec![exst!(NatLiteral(1))],
-        Some(vec![exst!(NatLiteral(2))]),
-        ))
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is \"gnosticism\" then 1 else 2",
-      exst!(
-        IfExpression {
-          discriminator: bx!(Discriminator::Simple(Meta::new(ex!(s "x")))),
-          body: bx!(IfExpressionBody::SimplePatternMatch(
-              Pattern::Literal(PatternLiteral::StringPattern(rc!(gnosticism))),
-              vec![exst!(s "1")],
-              Some(vec![exst!(s "2")]),
-              ))
-        }
-      )
-  }
-}

schala-lang/language/src/prelude.schala

@@ -1,14 +0,0 @@
-
-type Option<T> = Some(T) | None
-type Ord = LT | EQ | GT
-
-
-fn map(input: Option<T>, func: Func): Option<T> {
-  if input {
-    is Option::Some(x) -> Option::Some(func(x)),
-    is Option::None -> Option::None,
-  }
-}
-  
-
-type Complicated = Sunrise | Metal { black: bool, norwegian: bool } | Fella(String, Int)

schala-lang/language/src/reduced_ast.rs

@@ -1,516 +0,0 @@
-//! # Reduced AST
-//! The reduced AST is a minimal AST designed to be built from the full AST after all possible
-//! static checks have been done. Consequently, the AST reduction phase does very little error
-//! checking itself - any errors should ideally be caught either by an earlier phase, or are
-//! runtime errors that the evaluator should handle. That said, becuase it does do table lookups
-//! that can in principle fail [especially at the moment with most static analysis not yet complete],
-//! there is an Expr variant `ReductionError` to handle these cases.
-//!
-//! A design decision to make - should the ReducedAST types contain all information about
-//! type/layout necessary for the evaluator to work? If so, then the evaluator should not
-//! have access to the symbol table at all and ReducedAST should carry that information. If not,
-//! then ReducedAST shouldn't be duplicating information that can be queried at runtime from the
-//! symbol table. But I think the former might make sense since ultimately the bytecode will be
-//! built from the ReducedAST.
-use std::rc::Rc;
-use std::str::FromStr;
-
-use crate::ast::*;
-use crate::symbol_table::{Symbol, SymbolSpec, SymbolTable, FullyQualifiedSymbolName};
-use crate::builtin::Builtin;
-
-#[derive(Debug)]
-pub struct ReducedAST(pub Vec<Stmt>);
-
-#[derive(Debug, Clone)]
-pub enum Stmt {
-  PreBinding {
-    name: Rc<String>,
-    func: Func,
-  },
-  Binding {
-    name: Rc<String>,
-    constant: bool,
-    expr: Expr,
-  },
-  Expr(Expr),
-  Noop,
-}
-
-#[derive(Debug, Clone)]
-pub enum Expr {
-  Unit,
-  Lit(Lit),
-  Tuple(Vec<Expr>),
-  Func(Func),
-  Sym(Rc<String>),
-  Constructor {
-    type_name: Rc<String>,
-    name: Rc<String>,
-    tag: usize,
-    arity: usize, // n.b. arity here is always the value from the symbol table - if it doesn't match what it's being called with, that's an eval error, eval will handle it
-  },
-  Call {
-    f: Box<Expr>,
-    args: Vec<Expr>,
-  },
-  Assign {
-    val: Box<Expr>,
-    expr: Box<Expr>,
-  },
-  Conditional {
-    cond: Box<Expr>,
-    then_clause: Vec<Stmt>,
-    else_clause: Vec<Stmt>,
-  },
-  ConditionalTargetSigilValue,
-  CaseMatch {
-    cond: Box<Expr>,
-    alternatives: Vec<Alternative>
-  },
-  UnimplementedSigilValue,
-  ReductionError(String),
-}
-
-pub type BoundVars = Vec<Option<Rc<String>>>; //remember that order matters here
-
-#[derive(Debug, Clone)]
-pub struct Alternative {
-  pub matchable: Subpattern,
-  pub item: Vec<Stmt>,
-}
-
-#[derive(Debug, Clone)]
-pub struct Subpattern {
-  pub tag: Option<usize>,
-  pub subpatterns: Vec<Option<Subpattern>>,
-  pub bound_vars: BoundVars,
-  pub guard: Option<Expr>,
-}
-
-#[derive(Debug, Clone)]
-pub enum Lit {
-  Nat(u64),
-  Int(i64),
-  Float(f64),
-  Bool(bool),
-  StringLit(Rc<String>),
-}
-
-#[derive(Debug, Clone)]
-pub enum Func {
-  BuiltIn(Builtin),
-  UserDefined {
-    name: Option<Rc<String>>,
-    params: Vec<Rc<String>>,
-    body: Vec<Stmt>,
-  }
-}
-
-pub fn reduce(ast: &AST, symbol_table: &SymbolTable) -> ReducedAST {
-  let mut reducer = Reducer { symbol_table };
-  reducer.ast(ast)
-}
-
-struct Reducer<'a> {
-  symbol_table: &'a SymbolTable
-}
-
-impl<'a> Reducer<'a> {
-  fn ast(&mut self, ast: &AST) -> ReducedAST {
-    let mut output = vec![];
-    for statement in ast.statements.iter() {
-      output.push(self.statement(statement));
-    }
-    ReducedAST(output)
-  }
-
-  fn statement(&mut self, stmt: &Statement) -> Stmt {
-    match &stmt.kind {
-      StatementKind::Expression(expr) => Stmt::Expr(self.expression(&expr)),
-      StatementKind::Declaration(decl) => self.declaration(&decl),
-    }
-  }
-
-  fn block(&mut self, block: &Block) -> Vec<Stmt> {
-    block.iter().map(|stmt| self.statement(stmt)).collect()
-  }
-
-  fn invocation_argument(&mut self, invoc: &InvocationArgument) -> Expr {
-    use crate::ast::InvocationArgument::*;
-    match invoc {
-      Positional(ex) => self.expression(ex),
-      Keyword { .. } => Expr::UnimplementedSigilValue,
-      Ignored => Expr::UnimplementedSigilValue,
-    }
-  }
-
-  fn expression(&mut self, expr: &Expression) -> Expr {
-    use crate::ast::ExpressionKind::*;
-    let symbol_table = self.symbol_table;
-    let ref input = expr.kind;
-    match input {
-      NatLiteral(n) => Expr::Lit(Lit::Nat(*n)),
-      FloatLiteral(f) => Expr::Lit(Lit::Float(*f)),
-      StringLiteral(s) => Expr::Lit(Lit::StringLit(s.clone())),
-      BoolLiteral(b) => Expr::Lit(Lit::Bool(*b)),
-      BinExp(binop, lhs, rhs) => self.binop(binop, lhs, rhs),
-      PrefixExp(op, arg) => self.prefix(op, arg),
-      Value(qualified_name) => {
-        let ref id = qualified_name.id;
-        let ref sym_name = match symbol_table.get_fqsn_from_id(id) {
-          Some(fqsn) => fqsn,
-          None => return Expr::ReductionError(format!("FQSN lookup for Value {:?} failed", qualified_name)),
-        };
-        //TODO this probably needs to change
-        let FullyQualifiedSymbolName(ref v) = sym_name;
-        let name = v.last().unwrap().name.clone();
-        match symbol_table.lookup_by_fqsn(&sym_name) {
-          Some(Symbol { spec: SymbolSpec::DataConstructor { index, type_args, type_name}, .. }) => Expr::Constructor {
-            type_name: type_name.clone(),
-            name: name.clone(),
-            tag: index.clone(),
-            arity: type_args.len(),
-          },
-          _ => Expr::Sym(name.clone()),
-        }
-      },
-      Call { f, arguments } =>  self.reduce_call_expression(f, arguments),
-      TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| self.expression(e)).collect()),
-      IfExpression { discriminator, body } => self.reduce_if_expression(discriminator, body),
-      Lambda { params, body, .. } => self.reduce_lambda(params, body),
-      NamedStruct { name, fields } => self.reduce_named_struct(name, fields),
-      Index { .. } => Expr::UnimplementedSigilValue,
-      WhileExpression { .. } => Expr::UnimplementedSigilValue,
-      ForExpression { .. } => Expr::UnimplementedSigilValue,
-      ListLiteral { .. } => Expr::UnimplementedSigilValue,
-    }
-  }
-
-  fn reduce_lambda(&mut self, params: &Vec<FormalParam>, body: &Block) -> Expr {
-    Expr::Func(Func::UserDefined {
-      name: None,
-      params: params.iter().map(|param| param.name.clone()).collect(),
-      body: self.block(body),
-    })
-  }
-
-  fn reduce_named_struct(&mut self, name: &QualifiedName, fields: &Vec<(Rc<String>, Expression)>) -> Expr {
-    let symbol_table = self.symbol_table;
-    let ref sym_name = match symbol_table.get_fqsn_from_id(&name.id) {
-      Some(fqsn) => fqsn,
-      None => return Expr::ReductionError(format!("FQSN lookup for name {:?} failed", name)),
-    };
-
-    let FullyQualifiedSymbolName(ref v) = sym_name;
-    let ref name = v.last().unwrap().name;
-    let (type_name, index, members_from_table) = match symbol_table.lookup_by_fqsn(&sym_name) {
-      Some(Symbol { spec: SymbolSpec::RecordConstructor { members, type_name, index },  .. }) => (type_name.clone(), index, members),
-      _ => return Expr::ReductionError("Not a record constructor".to_string()),
-    };
-    let arity = members_from_table.len();
-
-    let mut args: Vec<(Rc<String>, Expr)> = fields.iter()
-      .map(|(name, expr)| (name.clone(), self.expression(expr)))
-      .collect();
-
-    args.as_mut_slice()
-      .sort_unstable_by(|(name1, _), (name2, _)| name1.cmp(name2)); //arbitrary - sorting by alphabetical order
-
-    let args = args.into_iter().map(|(_, expr)| expr).collect();
-
-    //TODO make sure this sorting actually works
-    let f = box Expr::Constructor { type_name, name: name.clone(), tag: *index, arity, };
-    Expr::Call { f, args }
-  }
-
-  fn reduce_call_expression(&mut self, func: &Expression, arguments: &Vec<InvocationArgument>) -> Expr {
-    Expr::Call {
-      f: Box::new(self.expression(func)),
-      args: arguments.iter().map(|arg| self.invocation_argument(arg)).collect(),
-    }
-  }
-
-  fn reduce_if_expression(&mut self, discriminator: &Discriminator, body: &IfExpressionBody) -> Expr {
-    let symbol_table = self.symbol_table;
-    let cond = Box::new(match *discriminator {
-      Discriminator::Simple(ref expr) => self.expression(expr),
-      Discriminator::BinOp(ref _expr, ref _binop) => panic!("Can't yet handle binop discriminators")
-    });
-    match *body {
-      IfExpressionBody::SimpleConditional(ref then_clause, ref else_clause) => {
-        let then_clause = self.block(then_clause);
-        let else_clause = match else_clause {
-          None => vec![],
-          Some(stmts) => self.block(stmts),
-        };
-        Expr::Conditional { cond, then_clause, else_clause }
-      },
-      IfExpressionBody::SimplePatternMatch(ref pat, ref then_clause, ref else_clause) => {
-        let then_clause = self.block(then_clause);
-        let else_clause = match else_clause {
-          None => vec![],
-          Some(stmts) => self.block(stmts),
-        };
-
-        let alternatives = vec![
-          pat.to_alternative(then_clause, symbol_table),
-          Alternative {
-            matchable: Subpattern {
-              tag: None,
-              subpatterns: vec![],
-              bound_vars: vec![],
-              guard: None,
-            },
-            item: else_clause
-          },
-        ];
-
-        Expr::CaseMatch {
-          cond,
-          alternatives,
-        }
-      },
-      IfExpressionBody::GuardList(ref guard_arms) => {
-        let mut alternatives = vec![];
-        for arm in guard_arms {
-          match arm.guard {
-            Guard::Pat(ref p) =>  {
-              let item = self.block(&arm.body);
-              let alt = p.to_alternative(item, symbol_table);
-              alternatives.push(alt);
-            },
-            Guard::HalfExpr(HalfExpr { op: _, expr: _ }) => {
-              return Expr::UnimplementedSigilValue
-            }
-          }
-        }
-        Expr::CaseMatch { cond, alternatives }
-      }
-    }
-  }
-
-  fn binop(&mut self, binop: &BinOp, lhs: &Box<Expression>, rhs: &Box<Expression>) -> Expr {
-    let operation = Builtin::from_str(binop.sigil()).ok();
-    match operation {
-      Some(Builtin::Assignment) => Expr::Assign {
-        val: Box::new(self.expression(&*lhs)),
-        expr: Box::new(self.expression(&*rhs)),
-      },
-      Some(op) => {
-        let f = Box::new(Expr::Func(Func::BuiltIn(op)));
-        Expr::Call { f, args: vec![self.expression(&*lhs), self.expression(&*rhs)] }
-      },
-      None => {
-        //TODO handle a user-defined operation
-        Expr::UnimplementedSigilValue
-      }
-    }
-  }
-
-  fn prefix(&mut self, prefix: &PrefixOp, arg: &Box<Expression>) -> Expr {
-    match prefix.builtin {
-      Some(op) => {
-        let f = Box::new(Expr::Func(Func::BuiltIn(op)));
-        Expr::Call { f, args: vec![self.expression(arg)] }
-      },
-      None => { //TODO need this for custom prefix ops
-        Expr::UnimplementedSigilValue
-      }
-    }
-  }
-
-  fn declaration(&mut self, declaration: &Declaration) -> Stmt {
-    use self::Declaration::*;
-    match declaration {
-      Binding {name, constant, expr, .. } => Stmt::Binding { name: name.clone(), constant: *constant, expr: self.expression(expr) },
-      FuncDecl(Signature { name, params, .. }, statements) => Stmt::PreBinding {
-        name: name.clone(),
-        func: Func::UserDefined {
-          name: Some(name.clone()),
-          params: params.iter().map(|param| param.name.clone()).collect(),
-          body: self.block(&statements),
-        }
-      },
-      TypeDecl { .. } => Stmt::Noop,
-      TypeAlias(_, _) => Stmt::Noop,
-      Interface { .. } => Stmt::Noop,
-      Impl { .. } => Stmt::Expr(Expr::UnimplementedSigilValue),
-      _ => Stmt::Expr(Expr::UnimplementedSigilValue)
-    }
-  }
-}
-
-
-
-
-
-/*                     ig var   pat
- * x is SomeBigOldEnum(_, x, Some(t))
- */
-
-fn handle_symbol(symbol: Option<&Symbol>, inner_patterns: &Vec<Pattern>, symbol_table: &SymbolTable) -> Subpattern {
-  use self::Pattern::*;
-  let tag = symbol.map(|symbol| match symbol.spec {
-    SymbolSpec::DataConstructor { index, .. } => index.clone(),
-    _ => panic!("Symbol is not a data constructor - this should've been caught in type-checking"),
-  });
-  let bound_vars = inner_patterns.iter().map(|p| match p {
-    VarOrName(qualified_name) => {
-      let fqsn = symbol_table.get_fqsn_from_id(&qualified_name.id);
-      let symbol_exists = fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)).is_some();
-      if symbol_exists {
-        None
-      } else {
-        let QualifiedName { components, .. } = qualified_name;
-        if components.len() == 1 {
-          Some(components[0].clone())
-        } else {
-          panic!("Bad variable name in pattern");
-        }
-      }
-    },
-    _ => None,
-  }).collect();
-
-  let subpatterns = inner_patterns.iter().map(|p| match p {
-    Ignored => None,
-    VarOrName(_) => None,
-    Literal(other) => Some(other.to_subpattern(symbol_table)),
-    tp @ TuplePattern(_) => Some(tp.to_subpattern(symbol_table)),
-    ts @ TupleStruct(_, _) => Some(ts.to_subpattern(symbol_table)),
-    Record(..) => unimplemented!(),
-  }).collect();
-
-  let guard = None;
-  /*
-     let guard_equality_exprs: Vec<Expr> = subpatterns.iter().map(|p| match p {
-     Literal(lit) => match lit {
-     _ => unimplemented!()
-     },
-     _ => unimplemented!()
-     }).collect();
-     */
-
-  Subpattern {
-    tag,
-    subpatterns,
-    guard,
-    bound_vars,
-  }
-}
-
-impl Pattern {
-  fn to_alternative(&self, item: Vec<Stmt>, symbol_table: &SymbolTable) -> Alternative {
-    let s = self.to_subpattern(symbol_table);
-    Alternative {
-      matchable: Subpattern {
-        tag: s.tag,
-        subpatterns: s.subpatterns,
-        bound_vars: s.bound_vars,
-        guard: s.guard,
-      },
-      item
-    }
-  }
-
-  fn to_subpattern(&self, symbol_table: &SymbolTable) -> Subpattern {
-    use self::Pattern::*;
-    match self {
-      TupleStruct(QualifiedName{ components, id }, inner_patterns) => {
-        let fqsn = symbol_table.get_fqsn_from_id(&id);
-        match fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)) {
-          Some(symbol) => handle_symbol(Some(symbol), inner_patterns, symbol_table),
-          None => {
-            panic!("Symbol {:?} not found", components);
-          }
-        }
-      },
-      TuplePattern(inner_patterns) => handle_symbol(None, inner_patterns, symbol_table),
-      Record(_name, _pairs) => {
-        unimplemented!()
-      },
-      Ignored => Subpattern { tag: None, subpatterns: vec![], guard: None, bound_vars: vec![] },
-      Literal(lit) => lit.to_subpattern(symbol_table),
-      VarOrName(QualifiedName { components, id  }) => {
-        // if fqsn is Some, treat this as a symbol pattern. If it's None, treat it
-        // as a variable.
-        println!("Calling VarOrName reduction with : {:?}", components);
-        let fqsn = symbol_table.get_fqsn_from_id(&id);
-        match fqsn.and_then(|fqsn| symbol_table.lookup_by_fqsn(&fqsn)) {
-          Some(symbol) => handle_symbol(Some(symbol), &vec![], symbol_table),
-          None => {
-            let name = if components.len() == 1 {
-              components[0].clone()
-            } else {
-              panic!("check this line of code yo");
-            };
-            Subpattern {
-              tag: None,
-              subpatterns: vec![],
-              guard: None,
-              bound_vars: vec![Some(name.clone())],
-            }
-          }
-        }
-      },
-    }
-  }
-}
-
-impl PatternLiteral {
-  fn to_subpattern(&self, _symbol_table: &SymbolTable) -> Subpattern {
-    use self::PatternLiteral::*;
-    match self {
-      NumPattern { neg, num } => {
-        let comparison = Expr::Lit(match (neg, num) {
-          (false, ExpressionKind::NatLiteral(n)) => Lit::Nat(*n),
-          (false, ExpressionKind::FloatLiteral(f)) => Lit::Float(*f),
-          (true, ExpressionKind::NatLiteral(n)) => Lit::Int(-1*(*n as i64)),
-          (true, ExpressionKind::FloatLiteral(f)) => Lit::Float(-1.0*f),
-          _ => panic!("This should never happen")
-        });
-        let guard = Some(Expr::Call {
-          f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
-          args: vec![comparison, Expr::ConditionalTargetSigilValue],
-        });
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-      StringPattern(s) => {
-        let guard = Some(Expr::Call {
-          f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
-          args: vec![Expr::Lit(Lit::StringLit(s.clone())), Expr::ConditionalTargetSigilValue]
-        });
-
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-      BoolPattern(b) =>  {
-        let guard = Some(if *b {
-          Expr::ConditionalTargetSigilValue
-        } else {
-          Expr::Call {
-            f: Box::new(Expr::Func(Func::BuiltIn(Builtin::BooleanNot))),
-            args: vec![Expr::ConditionalTargetSigilValue]
-          }
-        });
-        Subpattern {
-          tag: None,
-          subpatterns: vec![],
-          guard,
-          bound_vars: vec![],
-        }
-      },
-    }
-  }
-
-}

schala-lang/language/src/schala.rs

@@ -1,322 +0,0 @@
-use stopwatch::Stopwatch;
-
-use std::time::Duration;
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::collections::HashSet;
-
-use itertools::Itertools;
-use schala_repl::{ProgrammingLanguageInterface,
-ComputationRequest, ComputationResponse,
-LangMetaRequest, LangMetaResponse, GlobalOutputStats,
-DebugResponse, DebugAsk};
-use crate::{ast, reduced_ast, tokenizing, parsing, eval, typechecking, symbol_table};
-
-/// All the state necessary to parse and execute a Schala program are stored in this struct.
-/// `state` represents the execution state for the AST-walking interpreter, the other fields
-/// should be self-explanatory.
-pub struct Schala {
-  source_reference: SourceReference,
-  state: eval::State<'static>,
-  symbol_table: Rc<RefCell<symbol_table::SymbolTable>>,
-  type_context: typechecking::TypeContext<'static>,
-  active_parser: Option<parsing::Parser>,
-}
-
-impl Schala {
-  fn handle_docs(&self, source: String) -> LangMetaResponse {
-    LangMetaResponse::Docs {
-      doc_string: format!("Schala item `{}` : <<Schala-lang documentation not yet implemented>>", source)
-    }
-  }
-}
-
-impl Schala {
-  /// Creates a new Schala environment *without* any prelude.
-  fn new_blank_env() -> Schala {
-    let symbols = Rc::new(RefCell::new(symbol_table::SymbolTable::new()));
-    Schala {
-      source_reference: SourceReference::new(),
-      symbol_table: symbols.clone(),
-      state: eval::State::new(symbols),
-      type_context: typechecking::TypeContext::new(),
-      active_parser: None,
-    }
-  }
-
-  /// Creates a new Schala environment with the standard prelude, which is defined as ordinary
-  /// Schala code in the file `prelude.schala`
-  pub fn new() -> Schala {
-    let prelude = include_str!("prelude.schala");
-    let mut s = Schala::new_blank_env();
-
-    let request = ComputationRequest { source: prelude, debug_requests: HashSet::default() };
-    s.run_computation(request);
-    s
-  }
-
-  fn handle_debug_immediate(&self, request: DebugAsk) -> DebugResponse {
-    use DebugAsk::*;
-    match request {
-      Timing => DebugResponse { ask: Timing, value: format!("Invalid") },
-      ByStage { stage_name, token } => match &stage_name[..] {
-        "symbol-table" => {
-          let value = self.symbol_table.borrow().debug_symbol_table();
-          DebugResponse {
-            ask: ByStage { stage_name: format!("symbol-table"), token },
-            value
-          }
-        },
-        s => {
-          DebugResponse {
-            ask: ByStage { stage_name: s.to_string(), token: None },
-            value: format!("Not-implemented")
-          }
-        }
-      }
-    }
-  }
-}
-
-fn tokenizing(input: &str, _handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<Vec<tokenizing::Token>, String> {
-  let tokens = tokenizing::tokenize(input);
-  comp.map(|comp| {
-    let token_string = tokens.iter().map(|t| t.to_string_with_metadata()).join(", ");
-    comp.add_artifact(token_string);
-  });
-
-  let errors: Vec<String> = tokens.iter().filter_map(|t| t.get_error()).collect();
-  if errors.len() == 0 {
-    Ok(tokens)
-  } else {
-    Err(format!("{:?}", errors))
-  }
-}
-
-fn parsing(input: Vec<tokenizing::Token>, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  use crate::parsing::Parser;
-  use ParsingDebugType::*;
-
-  let mut parser = handle.active_parser.take().unwrap_or_else(|| Parser::new(input));
-  let ast = parser.parse();
-
-  comp.map(|comp| {
-    let debug_format = comp.parsing.as_ref().unwrap_or(&CompactAST);
-    let debug_info = match debug_format {
-      CompactAST => match ast{
-        Ok(ref ast) => ast.compact_debug(),
-        Err(_) => "Error - see output".to_string(),
-      },
-      ExpandedAST => match ast{
-        Ok(ref ast) => ast.expanded_debug(),
-        Err(_) => "Error - see output".to_string(),
-      },
-      Trace => parser.format_parse_trace(),
-    };
-    comp.add_artifact(debug_info);
-  });
-  ast.map_err(|err| format_parse_error(err, handle))
-}
-
-fn format_parse_error(error: parsing::ParseError, handle: &mut Schala) -> String {
-  let line_num = error.token.line_num;
-  let ch = error.token.char_num;
-  let line_from_program = handle.source_reference.get_line(line_num);
-  let location_pointer = format!("{}^", " ".repeat(ch));
-
-  let line_num_digits = format!("{}", line_num).chars().count();
-  let space_padding = " ".repeat(line_num_digits);
-
-  format!(r#"
-{error_msg}
-{space_padding} |
-{line_num} | {}
-{space_padding} | {}
-"#, line_from_program, location_pointer, error_msg=error.msg, space_padding=space_padding, line_num=line_num)
-}
-
-fn symbol_table(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let () = handle.symbol_table.borrow_mut().add_top_level_symbols(&input)?;
-  comp.map(|comp| {
-    let debug = handle.symbol_table.borrow().debug_symbol_table();
-    comp.add_artifact(debug);
-  });
-  Ok(input)
-}
-
-fn scope_resolution(mut input: ast::AST, handle: &mut Schala, _com: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let mut symbol_table = handle.symbol_table.borrow_mut();
-  let mut resolver = crate::scope_resolution::ScopeResolver::new(&mut symbol_table);
-  let () = resolver.resolve(&mut input)?;
-  Ok(input)
-}
-
-fn typechecking(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<ast::AST, String> {
-  let result = handle.type_context.typecheck(&input);
-
-  comp.map(|comp| {
-    comp.add_artifact(match result {
-      Ok(ty) => ty.to_string(),
-      Err(err) => format!("Type error: {}", err.msg)
-    });
-  });
-
-  Ok(input)
-}
-
-fn ast_reducing(input: ast::AST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<reduced_ast::ReducedAST, String> {
-  let ref symbol_table = handle.symbol_table.borrow();
-  let output = reduced_ast::reduce(&input, symbol_table);
-  comp.map(|comp| comp.add_artifact(format!("{:?}", output)));
-  Ok(output)
-}
-
-fn eval(input: reduced_ast::ReducedAST, handle: &mut Schala, comp: Option<&mut PassDebugArtifact>) -> Result<String, String> {
-  comp.map(|comp| comp.add_artifact(handle.state.debug_print()));
-  let evaluation_outputs = handle.state.evaluate(input, true);
-  let text_output: Result<Vec<String>, String> = evaluation_outputs
-    .into_iter()
-    .collect();
-
-  let eval_output: Result<String, String> = text_output
-    .map(|v| { v.into_iter().intersperse(format!("\n")).collect() });
-  eval_output
-}
-
-/// Represents lines of source code
-struct SourceReference {
-  lines: Option<Vec<String>>
-}
-
-impl SourceReference {
-  fn new() -> SourceReference {
-    SourceReference { lines: None }
-  }
-
-  fn load_new_source(&mut self, source: &str) {
-    //TODO this is a lot of heap allocations - maybe there's a way to make it more efficient?
-    self.lines = Some(source.lines().map(|s| s.to_string()).collect()); }
-
-  fn get_line(&self, line: usize) -> String {
-    self.lines.as_ref().and_then(|x| x.get(line).map(|s| s.to_string())).unwrap_or(format!("NO LINE FOUND"))
-  }
-}
-
-enum ParsingDebugType {
-  CompactAST,
-  ExpandedAST,
-  Trace
-}
-
-#[derive(Default)]
-struct PassDebugArtifact {
-  parsing: Option<ParsingDebugType>,
-  artifacts: Vec<String>
-
-}
-impl PassDebugArtifact {
-  fn add_artifact(&mut self, artifact: String) {
-    self.artifacts.push(artifact)
-  }
-}
-
-fn stage_names() -> Vec<&'static str> {
-  vec![
-    "tokenizing",
-    "parsing",
-    "symbol-table",
-    "scope-resolution",
-    "typechecking",
-    "ast-reduction",
-    "ast-walking-evaluation"
-  ]
-}
-
-
-impl ProgrammingLanguageInterface for Schala {
-  fn get_language_name(&self) -> String { format!("Schala") }
-  fn get_source_file_suffix(&self) -> String { format!("schala") }
-
-  fn run_computation(&mut self, request: ComputationRequest) -> ComputationResponse {
-    struct PassToken<'a> {
-      schala: &'a mut Schala,
-      stage_durations: &'a mut Vec<(String, Duration)>,
-      sw: &'a Stopwatch,
-      debug_requests: &'a HashSet<DebugAsk>,
-      debug_responses: &'a mut Vec<DebugResponse>,
-    }
-
-    fn output_wrapper<Input, Output, F>(n: usize, func: F, input: Input, token: &mut PassToken) -> Result<Output, String>
-      where F: Fn(Input, &mut Schala, Option<&mut PassDebugArtifact>) -> Result<Output, String>
-    {
-      let stage_names = stage_names();
-      let cur_stage_name = stage_names[n];
-      let ask = token.debug_requests.iter().find(|ask| ask.is_for_stage(cur_stage_name));
-
-      let parsing = match ask {
-        Some(DebugAsk::ByStage { token, .. }) if cur_stage_name == "parsing" => Some(
-          token.as_ref().map(|token| match &token[..] {
-            "compact" => ParsingDebugType::CompactAST,
-            "expanded" => ParsingDebugType::ExpandedAST,
-            "trace" => ParsingDebugType::Trace,
-            _ => ParsingDebugType::CompactAST,
-          }).unwrap_or(ParsingDebugType::CompactAST)
-        ),
-        _ => None,
-      };
-
-      let mut debug_artifact = ask.map(|_| PassDebugArtifact {
-        parsing, ..Default::default()
-      });
-
-      let output = func(input, token.schala, debug_artifact.as_mut());
-
-      //TODO I think this is not counting the time since the *previous* stage
-      token.stage_durations.push((cur_stage_name.to_string(), token.sw.elapsed()));
-      if let Some(artifact) = debug_artifact {
-        for value in artifact.artifacts.into_iter() {
-          let resp = DebugResponse { ask: ask.unwrap().clone(), value };
-          token.debug_responses.push(resp);
-        }
-      }
-      output
-    }
-
-    let ComputationRequest { source, debug_requests } = request;
-    self.source_reference.load_new_source(source);
-    let sw = Stopwatch::start_new();
-    let mut stage_durations = Vec::new();
-    let mut debug_responses = Vec::new();
-    let mut tok = PassToken { schala: self, stage_durations: &mut stage_durations, sw: &sw, debug_requests: &debug_requests, debug_responses: &mut debug_responses };
-
-    let main_output: Result<String, String> = Ok(source)
-      .and_then(|source| output_wrapper(0, tokenizing, source, &mut tok))
-      .and_then(|tokens| output_wrapper(1, parsing, tokens, &mut tok))
-      .and_then(|ast| output_wrapper(2, symbol_table, ast, &mut tok))
-      .and_then(|ast| output_wrapper(3, scope_resolution, ast, &mut tok))
-      .and_then(|ast| output_wrapper(4, typechecking, ast, &mut tok))
-      .and_then(|ast| output_wrapper(5, ast_reducing, ast, &mut tok))
-      .and_then(|reduced_ast| output_wrapper(6, eval, reduced_ast, &mut tok));
-
-    let total_duration = sw.elapsed();
-    let global_output_stats = GlobalOutputStats {
-      total_duration, stage_durations
-    };
-
-    ComputationResponse {
-      main_output,
-      global_output_stats,
-      debug_responses,
-    }
-  }
-
-  fn request_meta(&mut self, request: LangMetaRequest) -> LangMetaResponse {
-    match request {
-      LangMetaRequest::StageNames => LangMetaResponse::StageNames(stage_names().iter().map(|s| s.to_string()).collect()),
-      LangMetaRequest::Docs { source } => self.handle_docs(source),
-      LangMetaRequest::ImmediateDebug(debug_request) =>
-        LangMetaResponse::ImmediateDebug(self.handle_debug_immediate(debug_request)),
-      LangMetaRequest::Custom { .. } => LangMetaResponse::Custom { kind: format!("not-implemented"), value: format!("") }
-    }
-  }
-}

schala-lang/language/src/scope_resolution.rs

@@ -1,177 +0,0 @@
-use crate::symbol_table::{SymbolTable, ScopeSegment, ScopeSegmentKind, FullyQualifiedSymbolName};
-use crate::ast::*;
-
-pub struct ScopeResolver<'a> {
-  symbol_table: &'a mut SymbolTable
-}
-
-impl<'a> ScopeResolver<'a> {
-  pub fn new(symbol_table: &'a mut SymbolTable) -> ScopeResolver {
-    ScopeResolver { symbol_table }
-  }
-  pub fn resolve(&mut self, ast: &mut AST) -> Result<(), String> {
-    for statement in ast.statements.iter() {
-      match statement.kind {
-        StatementKind::Declaration(ref decl) => self.decl(decl),
-        StatementKind::Expression(ref expr) => self.expr(expr),
-      }?;
-    }
-    Ok(())
-  }
-
-  fn decl(&mut self, decl: &Declaration) -> Result<(), String> {
-    use Declaration::*;
-    match decl {
-      Binding { expr, .. } => self.expr(expr),
-      FuncDecl(_, block) => self.block(block),
-      _ => Ok(()),
-    }
-  }
-  fn block(&mut self, block: &Block) -> Result<(), String> {
-    for statement in block.iter() {
-      match statement.kind {
-        StatementKind::Declaration(ref decl) => self.decl(decl),
-        StatementKind::Expression(ref expr) => self.expr(expr),
-      }?;
-    }
-    Ok(())
-  }
-
-  fn expr(&mut self, expr: &Expression) -> Result<(), String> {
-    use ExpressionKind::*;
-    match &expr.kind {
-      ExpressionKind::Value(qualified_name) => {
-        let fqsn = lookup_name_in_scope(&qualified_name);
-        let ref id = qualified_name.id;
-        self.symbol_table.map_id_to_fqsn(id, fqsn);
-      },
-      NamedStruct {  name, .. } => {
-        let ref id = name.id;
-        let fqsn = lookup_name_in_scope(&name);
-        self.symbol_table.map_id_to_fqsn(id, fqsn);
-      },
-      BinExp(_, ref lhs, ref rhs) => {
-        self.expr(lhs)?;
-        self.expr(rhs)?;
-      },
-      PrefixExp(_, ref arg) => {
-        self.expr(arg)?;
-      },
-      TupleLiteral(exprs) => {
-        for expr in exprs.iter() {
-          self.expr(expr)?;
-        }
-      },
-      Call { f, arguments } => {
-        self.expr(&f)?;
-        for arg in arguments.iter() {
-          self.invoc(arg)?;
-        }
-      },
-      Lambda { params, body, .. } => { 
-        self.block(&body)?;
-        for param in params.iter() {
-          if let Some(ref expr) = param.default {
-            self.expr(expr)?;
-          }
-        }
-      },
-      IfExpression { ref body, ref discriminator } => {
-        match &**discriminator {
-          Discriminator::Simple(expr) | Discriminator::BinOp(expr, _) => self.expr(expr)?
-        };
-
-        match &**body {
-          IfExpressionBody::SimplePatternMatch(ref pat, ref alt1, ref alt2) => {
-            self.pattern(pat)?;
-            self.block(alt1)?;
-            if let Some(alt) = alt2 {
-              self.block(alt)?;
-            }
-          },
-          IfExpressionBody::GuardList(guardarms) => {
-            for arm in guardarms.iter() {
-              if let Guard::Pat(ref pat) = arm.guard {
-                self.pattern(pat)?;
-              }
-              self.block(&arm.body)?;
-            }
-          }
-          _ => ()
-        }
-      },
-      _ => ()
-    };
-    Ok(())
-  }
-
-  fn invoc(&mut self, invoc: &InvocationArgument) -> Result<(), String> {
-    use InvocationArgument::*;
-    match invoc {
-      Positional(expr) => self.expr(expr),
-      Keyword { expr, .. } => self.expr(expr),
-      _ => Ok(())
-    }
-  }
-
-  fn pattern(&mut self, pat: &Pattern) -> Result<(), String> {
-    use Pattern::*;
-    match pat {
-      Ignored => (),
-      TuplePattern(patterns) => {
-        for pat in patterns {
-          self.pattern(pat)?;
-        }
-      },
-      Literal(_) => (),
-      TupleStruct(name, patterns) => {
-        self.qualified_name_in_pattern(name);
-        for pat in patterns {
-          self.pattern(pat)?;
-        }
-      },
-      Record(name, key_patterns) => {
-        self.qualified_name_in_pattern(name);
-        for (_, pat) in key_patterns {
-          self.pattern(pat)?;
-        }
-      },
-      VarOrName(name) => {
-        self.qualified_name_in_pattern(name);
-      },
-    };
-    Ok(())
-  }
-
-  /// this might be a variable or a pattern. if a variable, set to none
-  fn qualified_name_in_pattern(&mut self, qualified_name: &QualifiedName) {
-    let ref id = qualified_name.id;
-    let fqsn = lookup_name_in_scope(qualified_name);
-    if self.symbol_table.lookup_by_fqsn(&fqsn).is_some() {
-      self.symbol_table.map_id_to_fqsn(&id, fqsn);
-    }
-  }
-}
-
-//TODO this is incomplete
-fn lookup_name_in_scope(sym_name: &QualifiedName) -> FullyQualifiedSymbolName {
-  let QualifiedName { components: vec, .. } = sym_name;
-  let len = vec.len();
-  let new_vec: Vec<ScopeSegment> = vec.iter().enumerate().map(|(i, name)| {
-    let kind = if i == (len - 1) {
-      ScopeSegmentKind::Terminal
-    } else {
-      ScopeSegmentKind::Type
-    };
-    ScopeSegment { name: name.clone(), kind }
-  }).collect();
-   FullyQualifiedSymbolName(new_vec)
-}
-
-#[cfg(test)]
-mod tests {
-  #[test]
-  fn basic_scope() {
-
-  }
-}

schala-lang/language/src/symbol_table.rs

@@ -1,464 +0,0 @@
-use std::collections::HashMap;
-use std::collections::hash_map::Entry;
-use std::rc::Rc;
-use std::fmt;
-use std::fmt::Write;
-
-use crate::ast;
-use crate::ast::{ItemId, TypeBody, TypeSingletonName, Signature, Statement, StatementKind};
-use crate::typechecking::TypeName;
-
-type LineNumber = u32;
-type SymbolTrackTable = HashMap<Rc<String>, LineNumber>;
-
-#[derive(PartialEq, Eq, Hash, Debug, Clone)]
-pub struct FullyQualifiedSymbolName(pub Vec<ScopeSegment>);
-
-impl fmt::Display for FullyQualifiedSymbolName {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let FullyQualifiedSymbolName(v) = self;
-    for segment in v {
-      write!(f, "::{}", segment)?;
-    }
-    Ok(())
-  }
-}
-
-#[derive(Debug, Clone, Eq, PartialEq, Hash)]
-pub struct ScopeSegment {
-  pub name: Rc<String>, //TODO maybe this could be a &str, for efficiency?
-  pub kind: ScopeSegmentKind,
-}
-
-impl fmt::Display for ScopeSegment {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    use ScopeSegmentKind::*;
-    let kind = match self.kind {
-      Function => "fn",
-      Type => "ty",
-      Terminal => "tr",
-    };
-    write!(f, "{}({})", self.name, kind)
-  }
-}
-
-impl ScopeSegment {
-  pub fn new(name: Rc<String>, kind: ScopeSegmentKind) ->  ScopeSegment {
-    ScopeSegment { name, kind }
-  }
-}
-
-#[derive(Debug, Clone, Eq, PartialEq, Hash)]
-pub enum ScopeSegmentKind {
-  Function,
-  Type,
-  Terminal,
-}
-
-#[allow(unused_macros)]
-macro_rules! fqsn {
-  ( $( $name:expr ; $kind:tt),* ) => {
-    {
-      let mut vec = vec![];
-      $(
-        vec.push(ScopeSegment::new(
-            Rc::new($name.to_string()),  
-            sym_path_kind!($kind),
-        ));
-      )*
-      FullyQualifiedSymbolName(vec)
-    }
-  };
-}
-
-#[allow(unused_macros)]
-macro_rules! sym_path_kind {
-  (fn) => { ScopeSegmentKind::Function };
-  (ty) => { ScopeSegmentKind::Type };
-  (tr) => { ScopeSegmentKind::Terminal };
-}
-
-//cf. p. 150 or so of Language Implementation Patterns
-pub struct SymbolTable {
-  symbol_path_to_symbol: HashMap<FullyQualifiedSymbolName, Symbol>,
-  id_to_fqsn: HashMap<ItemId, FullyQualifiedSymbolName>,
-}
-
-//TODO add various types of lookups here, maybe multiple hash tables internally?
-impl SymbolTable {
-  pub fn new() -> SymbolTable {
-    SymbolTable {
-      symbol_path_to_symbol: HashMap::new(),
-      id_to_fqsn: HashMap::new(),
-    }
-  }
-
-  pub fn map_id_to_fqsn(&mut self, id: &ItemId, fqsn: FullyQualifiedSymbolName) {
-    self.id_to_fqsn.insert(id.clone(), fqsn);
-  }
-
-  pub fn get_fqsn_from_id(&self, id: &ItemId) -> Option<FullyQualifiedSymbolName> {
-    self.id_to_fqsn.get(&id).cloned()
-  }
-
-  fn add_new_symbol(&mut self, name: &Rc<String>, scope_path: &Vec<ScopeSegment>, spec: SymbolSpec) {
-    let mut vec: Vec<ScopeSegment> = scope_path.clone();
-    vec.push(ScopeSegment { name: name.clone(), kind: ScopeSegmentKind::Terminal });
-    let fully_qualified_name = FullyQualifiedSymbolName(vec);
-    let symbol = Symbol { name: name.clone(), fully_qualified_name: fully_qualified_name.clone(), spec };
-    self.symbol_path_to_symbol.insert(fully_qualified_name, symbol);
-  }
-
-  pub fn lookup_by_fqsn(&self, fully_qualified_path: &FullyQualifiedSymbolName) -> Option<&Symbol> {
-    self.symbol_path_to_symbol.get(fully_qualified_path)
-  }
-}
-
-#[derive(Debug)]
-pub struct Symbol {
-  pub name: Rc<String>, //TODO does this need to be pub?
-  fully_qualified_name: FullyQualifiedSymbolName,
-  pub spec: SymbolSpec,
-}
-
-impl fmt::Display for Symbol {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    write!(f, "<Name: {}, Spec: {}>", self.name, self.spec)
-  }
-}
-
-#[derive(Debug)]
-pub enum SymbolSpec {
-  Func(Vec<TypeName>),
-  DataConstructor {
-    index: usize,
-    type_name: TypeName,
-    type_args: Vec<Rc<String>>,
-  },
-  RecordConstructor {
-    index: usize,
-    members: HashMap<Rc<String>, TypeName>,
-    type_name: TypeName,
-  },
-  Binding
-}
-
-impl fmt::Display for SymbolSpec {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    use self::SymbolSpec::*;
-    match self {
-      Func(type_names) => write!(f, "Func({:?})", type_names),
-      DataConstructor { index, type_name, type_args } => write!(f, "DataConstructor(idx: {})({:?} -> {})", index, type_args, type_name),
-      RecordConstructor { type_name, index, ..} => write!(f, "RecordConstructor(idx: {})(<members> -> {})", index, type_name),
-      Binding => write!(f, "Binding"),
-    }
-  }
-}
-
-impl SymbolTable {
-  /* note: this adds names for *forward reference* but doesn't actually create any types. solve that problem
-   * later */
-
-  pub fn add_top_level_symbols(&mut self, ast: &ast::AST) -> Result<(), String> {
-    let mut scope_name_stack = Vec::new();
-    self.add_symbols_from_scope(&ast.statements, &mut scope_name_stack)
-  }
-
-  fn add_symbols_from_scope<'a>(&'a mut self, statements: &Vec<Statement>, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    use self::ast::Declaration::*;
-
-    fn insert_and_check_duplicate_symbol(table: &mut SymbolTrackTable, name: &Rc<String>) -> Result<(), String> {
-      match table.entry(name.clone()) {
-        Entry::Occupied(o) => {
-          let line_number = o.get(); //TODO make this actually work
-          Err(format!("Duplicate definition: {}. It's already defined at {}", name, line_number))
-        },
-        Entry::Vacant(v) => {
-          let line_number = 0; //TODO should work
-          v.insert(line_number);
-          Ok(())
-        }
-      }
-    }
-
-    let mut seen_identifiers: SymbolTrackTable = HashMap::new();
-
-    for statement in statements.iter() {
-      if let Statement { kind: StatementKind::Declaration(decl), .. } = statement {
-        match decl {
-          FuncSig(ref signature) => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name)?;
-            self.add_function_signature(signature, scope_name_stack)?
-          }
-          FuncDecl(ref signature, ref body) => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name)?;
-            self.add_function_signature(signature, scope_name_stack)?;
-            scope_name_stack.push(ScopeSegment{
-              name: signature.name.clone(),
-              kind: ScopeSegmentKind::Function,
-            });
-            let output = self.add_symbols_from_scope(body, scope_name_stack);
-            let _ = scope_name_stack.pop();
-            output?
-          },
-          TypeDecl { name, body, mutable } => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &name.name)?;
-            //TODO add ScopeSegmentKind::Type here
-            self.add_type_decl(name, body, mutable, scope_name_stack)?
-          },
-          Binding { name, .. } => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, name)?;
-            self.add_new_symbol(name, scope_name_stack, SymbolSpec::Binding);
-          }
-          _ => ()
-        }
-      }
-    }
-    Ok(())
-  }
-  pub fn debug_symbol_table(&self) -> String {
-    let mut output = format!("Symbol table\n");
-    for (name, sym) in &self.symbol_path_to_symbol {
-      write!(output, "{} -> {}\n", name, sym).unwrap();
-    }
-    output
-  }
-
-  fn add_function_signature(&mut self, signature: &Signature, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    let mut local_type_context = LocalTypeContext::new();
-    let types = signature.params.iter().map(|param| match param.anno {
-      Some(ref type_identifier) => Rc::new(format!("{:?}", type_identifier)),
-      None => local_type_context.new_universal_type()
-    }).collect();
-    self.add_new_symbol(&signature.name, scope_name_stack, SymbolSpec::Func(types));
-    Ok(())
-  }
-
-  //TODO handle type mutability
-  fn add_type_decl(&mut self, type_name: &TypeSingletonName, body: &TypeBody, _mutable: &bool, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
-    use crate::ast::{TypeIdentifier, Variant};
-    let TypeBody(variants) = body;
-    let ref type_name = type_name.name;
-    scope_name_stack.push(ScopeSegment{
-      name: type_name.clone(),
-      kind: ScopeSegmentKind::Type,
-    });
-    //TODO figure out why _params isn't being used here
-    for (index, var) in variants.iter().enumerate() {
-      match var {
-        Variant::UnitStruct(variant_name) => {
-          let spec = SymbolSpec::DataConstructor {
-            index,
-            type_name: type_name.clone(),
-            type_args: vec![],
-          };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
-        },
-        Variant::TupleStruct(variant_name, tuple_members) => {
-          //TODO fix the notion of a tuple type
-          let type_args = tuple_members.iter().map(|type_name| match type_name {
-            TypeIdentifier::Singleton(TypeSingletonName { name, ..}) => name.clone(),
-            TypeIdentifier::Tuple(_) => unimplemented!(),
-          }).collect();
-          let spec = SymbolSpec::DataConstructor {
-            index,
-            type_name: type_name.clone(),
-            type_args
-          };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
-        },
-        Variant::Record { name, members: defined_members } => {
-          let mut members = HashMap::new();
-          let mut duplicate_member_definitions = Vec::new();
-          for (member_name, member_type) in defined_members {
-            match members.entry(member_name.clone()) {
-              Entry::Occupied(_) => duplicate_member_definitions.push(member_name.clone()),
-              Entry::Vacant(v) => {
-                v.insert(match member_type {
-                  TypeIdentifier::Singleton(TypeSingletonName { name, ..}) => name.clone(),
-                  TypeIdentifier::Tuple(_) => unimplemented!(),
-                });
-              }
-            }
-          }
-          if duplicate_member_definitions.len() != 0 {
-            return Err(format!("Duplicate member(s) in definition of type {}: {:?}", type_name, duplicate_member_definitions));
-          }
-          let spec = SymbolSpec::RecordConstructor { index, type_name: type_name.clone(), members };
-          self.add_new_symbol(name, scope_name_stack, spec);
-        },
-      }
-    }
-    scope_name_stack.pop();
-    Ok(())
-  }
-}
-
-struct LocalTypeContext {
-  state: u8
-}
-impl LocalTypeContext {
-  fn new() -> LocalTypeContext {
-    LocalTypeContext { state: 0 }
-  }
-
-  fn new_universal_type(&mut self) -> TypeName {
-    let n = self.state;
-    self.state += 1;
-    Rc::new(format!("{}", (('a' as u8) + n) as char))
-  }
-}
-
-
-#[cfg(test)]
-mod symbol_table_tests {
-  use super::*;
-  use crate::util::quick_ast;
-
-  macro_rules! values_in_table {
-    //TODO multiple values
-    ($source:expr, $single_value:expr) => {
-      {
-      let mut symbol_table = SymbolTable::new();
-      let ast = quick_ast($source);
-      symbol_table.add_top_level_symbols(&ast).unwrap();
-      match symbol_table.lookup_by_fqsn($single_value) {
-        Some(_spec) => (),
-        None => panic!(),
-      };
-      }
-    }
-  }
-
-  #[test]
-  fn basic_symbol_table() {
-    values_in_table! { "let a = 10; fn b() { 20 }", &fqsn!("b"; tr) }
-  }
-
-  #[test]
-  fn no_duplicates() {
-    let source = r#"
-    fn a() { 1 }
-    fn b() { 2 }
-    fn a() { 3 }
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn no_duplicates_2() {
-    let source = r#"
-    let a = 20;
-    let q = 39;
-    let a = 30;
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn no_duplicates_3() {
-    let source = r#"
-    fn a() {
-      let a = 20
-      let b = 40
-      a + b
-    }
-
-    fn q() {
-      let x = 30
-      let x = 33
-    }
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-
-  #[test]
-  fn dont_falsely_detect_duplicates() {
-    let source = r#"
-    let a = 20;
-    fn some_func() {
-      let a = 40;
-      77
-    }
-    let q = 39;
-    "#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!["a"; tr]).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!["some_func"; fn, "a";tr]).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-  x + inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes_2() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-
-  fn second_inner_func() {
-    fn another_inner_func() {
-    }
-  }
-
-  inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    symbol_table.add_top_level_symbols(&ast).unwrap();
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "inner_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; tr)).is_some());
-    assert!(symbol_table.lookup_by_fqsn(&fqsn!("outer_func"; fn, "second_inner_func"; fn, "another_inner_func"; tr)).is_some());
-  }
-
-  #[test]
-  fn enclosing_scopes_3() {
-    let source = r#"
-fn outer_func(x) {
-  fn inner_func(arg) {
-    arg
-  }
-
-  fn second_inner_func() {
-    fn another_inner_func() {
-    }
-    fn another_inner_func() {
-    }
-  }
-
-  inner_func(x)
-}"#;
-    let mut symbol_table = SymbolTable::new();
-    let ast = quick_ast(source);
-    let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-    assert!(output.contains("Duplicate"))
-  }
-}
-

schala-lang/language/src/typechecking.rs

@@ -1,484 +0,0 @@
-use std::rc::Rc;
-use std::fmt::Write;
-
-use ena::unify::{UnifyKey, InPlaceUnificationTable, UnificationTable, EqUnifyValue};
-
-use crate::ast::*;
-use crate::util::ScopeStack;
-
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct TypeData {
-  ty: Option<Type>
-}
-
-impl TypeData {
-  pub fn new() -> TypeData {
-    TypeData { ty: None }
-  }
-}
-
-pub type TypeName = Rc<String>;
-
-pub struct TypeContext<'a> {
-  variable_map: ScopeStack<'a, Rc<String>, Type>,
-  unification_table: InPlaceUnificationTable<TypeVar>,
-}
-
-/// `InferResult` is the monad in which type inference takes place.
-type InferResult<T> = Result<T, TypeError>;
-
-#[derive(Debug, Clone)]
-pub struct TypeError { pub msg: String }
-
-impl TypeError {
-  fn new<A, T>(msg: T) -> InferResult<A> where T: Into<String> {
-    Err(TypeError { msg: msg.into() })
-  }
-}
-
-#[allow(dead_code)] // avoids warning from Compound
-#[derive(Debug, Clone, PartialEq)]
-pub enum Type {
-  Const(TypeConst),
-  Var(TypeVar),
-  Arrow {
-    params: Vec<Type>,
-    ret: Box<Type>
-  },
-  Compound {
-    ty_name: String,
-    args:Vec<Type>
-  }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct TypeVar(usize);
-
-impl UnifyKey for TypeVar {
-  type Value = Option<TypeConst>;
-  fn index(&self) -> u32 { self.0 as u32 }
-  fn from_index(u: u32) -> TypeVar { TypeVar(u as usize) }
-  fn tag() -> &'static str { "TypeVar" }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub enum TypeConst {
-  Unit,
-  Nat,
-  Int,
-  Float,
-  StringT,
-  Bool,
-  Ordering,
-  //UserDefined
-}
-
-impl TypeConst {
-  pub fn to_string(&self) -> String {
-    use self::TypeConst::*;
-    match self {
-      Unit => format!("()"),
-      Nat => format!("Nat"),
-      Int => format!("Int"),
-      Float => format!("Float"),
-      StringT => format!("String"),
-      Bool => format!("Bool"),
-      Ordering => format!("Ordering"),
-    }
-  }
-}
-
-impl EqUnifyValue for TypeConst { }
-
-macro_rules! ty {
-  ($type_name:ident) => { Type::Const(TypeConst::$type_name) };
-  ($t1:ident -> $t2:ident) => { Type::Arrow { params: vec![ty!($t1)], ret: box ty!($t2) } };
-  ($t1:ident -> $t2:ident -> $t3:ident) => { Type::Arrow { params: vec![ty!($t1), ty!($t2)], ret: box ty!($t3) } };
-  ($type_list:ident, $ret_type:ident) => {
-    Type::Arrow {
-      params: $type_list,
-      ret: box $ret_type,
-    }
-  }
-}
-
-//TODO find a better way to capture the to/from string logic
-impl Type {
-  pub fn to_string(&self) -> String {
-    use self::Type::*;
-    match self {
-      Const(c) => c.to_string(),
-      Var(v) => format!("t_{}", v.0),
-      Arrow { params, box ref ret } => {
-        if params.len() == 0 {
-          format!("-> {}", ret.to_string())
-        } else {
-          let mut buf = String::new();
-          for p in params.iter() {
-            write!(buf, "{} -> ", p.to_string()).unwrap();
-          }
-          write!(buf, "{}", ret.to_string()).unwrap();
-          buf
-        }
-      },
-      Compound { .. } => format!("<some compound type>")
-    }
-  }
-
-  fn from_string(string: &str) -> Option<Type> {
-    Some(match string {
-      "()" | "Unit" => ty!(Unit),
-      "Nat" => ty!(Nat),
-      "Int" => ty!(Int),
-      "Float" => ty!(Float),
-      "String" => ty!(StringT),
-      "Bool" => ty!(Bool),
-      "Ordering" => ty!(Ordering),
-      _ => return None
-    })
-  }
-}
-
-/*
-/// `Type` is parameterized by whether the type variables can be just universal, or universal or
-/// existential.
-#[derive(Debug, Clone)]
-enum Type<A> {
-  Var(A),
-  Const(TConst),
-  Arrow(Box<Type<A>>, Box<Type<A>>),
-}
-
-#[derive(Debug, Clone)]
-enum TVar {
-  Univ(UVar),
-  Exist(ExistentialVar)
-}
-
-#[derive(Debug, Clone)]
-struct UVar(Rc<String>);
-
-#[derive(Debug, Clone)]
-struct ExistentialVar(u32);
-
-impl Type<UVar> {
-  fn to_tvar(&self) -> Type<TVar> {
-    match self {
-      Type::Var(UVar(name)) => Type::Var(TVar::Univ(UVar(name.clone()))),
-      Type::Const(ref c) => Type::Const(c.clone()),
-      Type::Arrow(a, b) => Type::Arrow(
-        Box::new(a.to_tvar()),
-        Box::new(b.to_tvar())
-      )
-    }
-  }
-}
-
-impl Type<TVar> {
-  fn skolemize(&self) -> Type<UVar> {
-    match self {
-      Type::Var(TVar::Univ(uvar)) => Type::Var(uvar.clone()),
-      Type::Var(TVar::Exist(_)) => Type::Var(UVar(Rc::new(format!("sk")))),
-      Type::Const(ref c) => Type::Const(c.clone()),
-      Type::Arrow(a, b) => Type::Arrow(
-        Box::new(a.skolemize()),
-        Box::new(b.skolemize())
-      )
-    }
-  }
-}
-
-impl TypeIdentifier {
-  fn to_monotype(&self) -> Type<UVar> {
-    match self {
-      TypeIdentifier::Tuple(_) => Type::Const(TConst::Nat),
-      TypeIdentifier::Singleton(TypeSingletonName { name, .. }) => {
-        match &name[..] {
-          "Nat" => Type::Const(TConst::Nat),
-          "Int" => Type::Const(TConst::Int),
-          "Float" => Type::Const(TConst::Float),
-          "Bool" => Type::Const(TConst::Bool),
-          "String" => Type::Const(TConst::StringT),
-          _ => Type::Const(TConst::Nat),
-        }
-      }
-    }
-  }
-}
-
-#[derive(Debug, Clone)]
-enum TConst {
-  User(Rc<String>),
-  Unit,
-  Nat,
-  Int,
-  Float,
-  StringT,
-  Bool,
-}
-
-impl TConst {
-  fn user(name: &str) -> TConst {
-    TConst::User(Rc::new(name.to_string()))
-  }
-}
-*/
-
-impl<'a> TypeContext<'a> {
-  pub fn new() -> TypeContext<'a> {
-    TypeContext { 
-      variable_map: ScopeStack::new(None),
-      unification_table: UnificationTable::new(),
-    }
-  }
-
-  /*
-  fn new_env(&'a self, new_var: Rc<String>, ty: Type) -> TypeContext<'a> {
-    let mut new_context = TypeContext {
-      variable_map: self.variable_map.new_scope(None),
-      unification_table: UnificationTable::new(), //???? not sure if i want this
-    };
-
-    new_context.variable_map.insert(new_var, ty);
-    new_context
-  }
-  */
-
-
-  fn get_type_from_name(&self, name: &TypeIdentifier) -> InferResult<Type> {
-    use self::TypeIdentifier::*;
-    Ok(match name {
-      Singleton(TypeSingletonName { name,.. }) =>  {
-        match Type::from_string(&name) {
-          Some(ty) => ty,
-          None => return TypeError::new(format!("Unknown type name: {}", name))
-        }
-      },
-      Tuple(_) => return TypeError::new("tuples aren't ready yet"),
-    })
-  }
-
-  /// `typecheck` is the entry into the type-inference system, accepting an AST as an argument
-  /// Following the example of GHC, the compiler deliberately does typechecking before de-sugaring
-  /// the AST to ReducedAST
-  pub fn typecheck(&mut self, ast: &AST) -> Result<Type, TypeError> {
-    let mut returned_type = Type::Const(TypeConst::Unit);
-    for statement in ast.statements.iter() {
-      returned_type = self.statement(statement)?;
-    }
-    Ok(returned_type)
-  }
-
-  fn statement(&mut self, statement: &Statement) -> InferResult<Type> {
-    match &statement.kind {
-      StatementKind::Expression(e) => self.expr(e),
-      StatementKind::Declaration(decl) => self.decl(&decl),
-    }
-  }
-
-  fn decl(&mut self, decl: &Declaration) -> InferResult<Type> {
-    use self::Declaration::*;
-    match decl {
-      Binding { name, expr, .. } => {
-        let ty = self.expr(expr)?;
-        self.variable_map.insert(name.clone(), ty);
-      },
-      _ => (),
-    }
-    Ok(ty!(Unit))
-  }
-
-  fn invoc(&mut self, invoc: &InvocationArgument) -> InferResult<Type> {
-    use InvocationArgument::*;
-    match invoc {
-      Positional(expr) => self.expr(expr),
-      _ => Ok(ty!(Nat)) //TODO this is wrong
-    }
-  }
-
-  fn expr(&mut self, expr: &Expression) -> InferResult<Type> {
-    match expr {
-      Expression { kind, type_anno: Some(anno), .. } => {
-        let t1 = self.expr_type(kind)?;
-        let t2 = self.get_type_from_name(anno)?;
-        self.unify(t2, t1)
-      },
-      Expression { kind, type_anno: None, .. } => self.expr_type(kind)
-    }
-  }
-
-  fn expr_type(&mut self, expr: &ExpressionKind) -> InferResult<Type> {
-    use self::ExpressionKind::*;
-    Ok(match expr {
-      NatLiteral(_) => ty!(Nat),
-      BoolLiteral(_) => ty!(Bool),
-      FloatLiteral(_) => ty!(Float),
-      StringLiteral(_) => ty!(StringT),
-      PrefixExp(op, expr) => self.prefix(op, expr)?,
-      BinExp(op, lhs, rhs) => self.binexp(op, lhs, rhs)?,
-      IfExpression { discriminator, body } => self.if_expr(discriminator, body)?,
-      Value(val) => self.handle_value(val)?,
-      Call { box ref f, arguments } => self.call(f, arguments)?,
-      Lambda { params, type_anno, body } => self.lambda(params, type_anno, body)?,
-      _ => ty!(Unit),
-    })
-  }
-
-  fn prefix(&mut self, op: &PrefixOp, expr: &Expression) -> InferResult<Type> {
-    let tf = match op.builtin.map(|b| b.get_type()) {
-      Some(ty) => ty,
-      None => return TypeError::new("no type found")
-    };
-
-    let tx = self.expr(expr)?;
-    self.handle_apply(tf, vec![tx])
-  }
-
-  fn binexp(&mut self, op: &BinOp, lhs: &Expression, rhs: &Expression) -> InferResult<Type> {
-    let tf = match op.builtin.map(|b| b.get_type()) {
-      Some(ty) => ty,
-      None => return TypeError::new("no type found"),
-    };
-
-    let t_lhs = self.expr(lhs)?;
-    let t_rhs = self.expr(rhs)?; //TODO is this order a problem? not sure
-
-    self.handle_apply(tf, vec![t_lhs, t_rhs])
-  }
-
-  fn if_expr(&mut self, discriminator: &Discriminator, body: &IfExpressionBody) -> InferResult<Type> {
-    use self::Discriminator::*; use self::IfExpressionBody::*;
-    match (discriminator, body) {
-      (Simple(expr), SimpleConditional(then_clause, else_clause)) => self.handle_simple_if(expr, then_clause, else_clause),
-      _ => TypeError::new(format!("Complex conditionals not supported"))
-    }
-  }
-
-  fn handle_simple_if(&mut self, expr: &Expression, then_clause: &Block, else_clause: &Option<Block>) -> InferResult<Type> {
-    let t1 = self.expr(expr)?;
-    let t2 = self.block(then_clause)?;
-    let t3 = match else_clause {
-      Some(block) => self.block(block)?,
-      None => ty!(Unit)
-    };
-
-    let _ = self.unify(ty!(Bool), t1)?;
-    self.unify(t2, t3)
-  }
-
-  fn lambda(&mut self, params: &Vec<FormalParam>, type_anno: &Option<TypeIdentifier>, _body: &Block) -> InferResult<Type> {
-    let argument_types: InferResult<Vec<Type>> = params.iter().map(|param: &FormalParam| {
-      if let FormalParam { anno: Some(type_identifier), ..  } = param {
-        self.get_type_from_name(type_identifier)
-      } else {
-        Ok(Type::Var(self.fresh_type_variable()))
-      }
-    }).collect();
-    let argument_types = argument_types?;
-    let ret_type = match type_anno.as_ref() {
-      Some(anno) => self.get_type_from_name(anno)?,
-      None => Type::Var(self.fresh_type_variable())
-    };
-
-    Ok(ty!(argument_types, ret_type))
-  }
-
-  fn call(&mut self, f: &Expression, args: &Vec<InvocationArgument>) -> InferResult<Type> {
-    let tf = self.expr(f)?;
-    let arg_types: InferResult<Vec<Type>> = args.iter().map(|ex| self.invoc(ex)).collect();
-    let arg_types = arg_types?;
-    self.handle_apply(tf, arg_types)
-  }
-
-  fn handle_apply(&mut self, tf: Type, args: Vec<Type>) -> InferResult<Type> {
-    Ok(match tf {
-      Type::Arrow { ref params, ret: box ref t_ret } if params.len() == args.len() => {
-        for (t_param, t_arg) in params.iter().zip(args.iter()) {
-          let _ = self.unify(t_param.clone(), t_arg.clone())?; //TODO I think this needs to reference a sub-scope
-        }
-        t_ret.clone()
-      },
-      Type::Arrow { .. } => return TypeError::new("Wrong length"),
-      _ => return TypeError::new(format!("Not a function"))
-    })
-  }
-
-  fn block(&mut self, block: &Block) -> InferResult<Type> {
-    let mut output = ty!(Unit);
-    for statement in block.iter() {
-      output = self.statement(statement)?;
-    }
-    Ok(output)
-  }
-
-  fn handle_value(&mut self, val: &QualifiedName) -> InferResult<Type> {
-    let QualifiedName { components: vec, .. } = val;
-    let var = &vec[0];
-    match self.variable_map.lookup(var) {
-      Some(ty) => Ok(ty.clone()),
-      None => TypeError::new(format!("Couldn't find variable: {}", &var)),
-    }
-  }
-
-  fn unify(&mut self, t1: Type, t2: Type) -> InferResult<Type> {
-    use self::Type::*;
-
-    match (t1, t2) {
-      (Const(ref c1), Const(ref c2)) if c1 == c2 => Ok(Const(c1.clone())), //choice of c1 is arbitrary I *think*
-      (a @ Var(_), b @ Const(_)) => self.unify(b, a),
-      (Const(ref c1), Var(ref v2)) => {
-        self.unification_table.unify_var_value(v2.clone(), Some(c1.clone()))
-          .or_else(|_| TypeError::new(format!("Couldn't unify {:?} and {:?}", Const(c1.clone()), Var(*v2))))?;
-        Ok(Const(c1.clone()))
-      },
-      (Var(v1), Var(v2)) => {
-        //TODO add occurs check
-        self.unification_table.unify_var_var(v1.clone(), v2.clone())
-          .or_else(|e| {
-            println!("Unify error: {:?}", e);
-            TypeError::new(format!("Two type variables {:?} and {:?} couldn't unify", v1, v2))
-          })?;
-        Ok(Var(v1.clone())) //arbitrary decision I think
-      },
-      (a, b) => TypeError::new(format!("{:?} and {:?} do not unify", a, b)),
-    }
-  }
-
-  fn fresh_type_variable(&mut self) -> TypeVar {
-    let new_type_var = self.unification_table.new_key(None);
-    new_type_var
-  }
-}
-
-#[cfg(test)]
-mod typechecking_tests {
-  use super::*;
-
-  macro_rules! assert_type_in_fresh_context {
-    ($string:expr, $type:expr) => {
-      let mut tc = TypeContext::new();
-      let ref ast = crate::util::quick_ast($string);
-      let ty = tc.typecheck(ast).unwrap();
-      assert_eq!(ty, $type)
-    }
-  }
-
-  #[test]
-  fn basic_test() {
-    assert_type_in_fresh_context!("1", ty!(Nat));
-    assert_type_in_fresh_context!(r#""drugs""#, ty!(StringT));
-    assert_type_in_fresh_context!("true", ty!(Bool));
-  }
-
-  #[test]
-  fn operators() {
-    //TODO fix these with new operator regime
-    /*
-    assert_type_in_fresh_context!("-1", ty!(Int));
-    assert_type_in_fresh_context!("1 + 2", ty!(Nat));
-    assert_type_in_fresh_context!("-2", ty!(Int));
-    assert_type_in_fresh_context!("!true", ty!(Bool));
-    */
-  }
-}

schala-lang/src/ast.rs

@@ -0,0 +1,180 @@
+use std::rc::Rc;
+
+use builtin::{BinOp, PrefixOp};
+
+#[derive(Debug, PartialEq)]
+pub struct AST(pub Vec<Statement>);
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Statement {
+  ExpressionStatement(Expression),
+  Declaration(Declaration),
+}
+
+pub type Block = Vec<Statement>;
+
+pub type ParamName = Rc<String>;
+pub type InterfaceName = Rc<String>; //should be a singleton I think??
+pub type FormalParam = (ParamName, Option<TypeName>);
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Declaration {
+  FuncSig(Signature),
+  FuncDecl(Signature, Block),
+  TypeDecl {
+    name: TypeSingletonName,
+    body: TypeBody,
+    mutable: bool
+  },
+  TypeAlias(Rc<String>, Rc<String>), //should have TypeSingletonName in it, or maybe just String, not sure
+  Binding {
+    name: Rc<String>,
+    constant: bool,
+    expr: Expression,
+  },
+  Impl {
+    type_name: TypeName,
+    interface_name: Option<InterfaceName>,
+    block: Vec<Declaration>,
+  },
+  Interface {
+    name: Rc<String>,
+    signatures: Vec<Signature>
+  }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct Signature {
+  pub name: Rc<String>,
+  pub operator: bool,
+  pub params: Vec<FormalParam>,
+  pub type_anno: Option<TypeName>,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct TypeBody(pub Vec<Variant>);
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Variant {
+  UnitStruct(Rc<String>),
+  TupleStruct(Rc<String>, Vec<TypeName>),
+  Record(Rc<String>, Vec<(Rc<String>, TypeName)>),
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct Expression(pub ExpressionType, pub Option<TypeName>);
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum TypeName {
+  Tuple(Vec<TypeName>),
+  Singleton(TypeSingletonName)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct TypeSingletonName {
+  pub name: Rc<String>,
+  pub params: Vec<TypeName>,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum ExpressionType {
+  NatLiteral(u64),
+  FloatLiteral(f64),
+  StringLiteral(Rc<String>),
+  BoolLiteral(bool),
+  BinExp(BinOp, Box<Expression>, Box<Expression>),
+  PrefixExp(PrefixOp, Box<Expression>),
+  TupleLiteral(Vec<Expression>),
+  Value(Rc<String>),
+  NamedStruct {
+    name: Rc<String>,
+    fields: Vec<(Rc<String>, Expression)>,
+  },
+  Call {
+    f: Box<Expression>,
+    arguments: Vec<Expression>,
+  },
+  Index {
+    indexee: Box<Expression>,
+    indexers: Vec<Expression>,
+  },
+  IfExpression {
+    discriminator: Box<Discriminator>,
+    body: Box<IfExpressionBody>,
+  },
+  WhileExpression {
+    condition: Option<Box<Expression>>,
+    body: Block,
+  },
+  ForExpression {
+    enumerators: Vec<Enumerator>,
+    body: Box<ForBody>,
+  },
+  Lambda {
+    params: Vec<FormalParam>,
+    body: Block,
+  },
+  ListLiteral(Vec<Expression>),
+}
+#[derive(Debug, PartialEq, Clone)]
+pub enum Discriminator {
+  Simple(Expression),
+  BinOp(Expression, BinOp)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum IfExpressionBody {
+  SimpleConditional(Block, Option<Block>),
+  SimplePatternMatch(Pattern, Block, Option<Block>),
+  GuardList(Vec<GuardArm>)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct GuardArm {
+  pub guard: Guard,
+  pub body: Block,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Guard {
+  Pat(Pattern),
+  HalfExpr(HalfExpr)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct HalfExpr {
+  pub op: Option<BinOp>,
+  pub expr: ExpressionType,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum Pattern {
+  Ignored,
+  TuplePattern(Vec<Pattern>),
+  Literal(PatternLiteral),
+  TupleStruct(Rc<String>, Vec<Pattern>),
+  Record(Rc<String>, Vec<(Rc<String>, Pattern)>),
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum PatternLiteral {
+  NumPattern {
+    neg: bool,
+    num: ExpressionType,
+  },
+  StringPattern(Rc<String>),
+  BoolPattern(bool),
+  VarPattern(Rc<String>)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct Enumerator {
+  pub id: Rc<String>,
+  pub generator: Expression,
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum ForBody {
+  MonadicReturn(Expression),
+  StatementBlock(Block),
+}

schala-lang/src/builtin.rs

@@ -0,0 +1,138 @@
+use std::rc::Rc;
+use std::collections::HashMap;
+use std::fmt;
+
+use tokenizing::TokenType;
+use self::BuiltinTypeSpecifier::*;
+use self::BuiltinTConst::*;
+
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum BuiltinTypeSpecifier {
+  Const(BuiltinTConst),
+  Func(Box<BuiltinTypeSpecifier>, Box<BuiltinTypeSpecifier>),
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum BuiltinTConst {
+  Nat,
+  Int,
+  Float,
+  StringT,
+  Bool,
+}
+
+impl fmt::Display for BuiltinTypeSpecifier {
+  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    write!(f, "{:?}", self)
+  }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct BinOp {
+  sigil: Rc<String>
+}
+
+impl BinOp {
+  pub fn from_sigil(sigil: &str) -> BinOp {
+    BinOp { sigil: Rc::new(sigil.to_string()) }
+  }
+  pub fn sigil(&self) -> &Rc<String> {
+    &self.sigil
+  }
+  pub fn from_sigil_token(tok: &TokenType) -> Option<BinOp> {
+    use self::TokenType::*;
+    let s = match tok {
+      Operator(op) => op,
+      Period => ".",
+      Pipe => "|",
+      Slash => "/",
+      LAngleBracket => "<",
+      RAngleBracket => ">",
+      _ => return None
+    };
+    Some(BinOp::from_sigil(s))
+  }
+  /*
+  pub fn get_type(&self) -> Result<Type, String> {
+    let s = self.sigil.as_str();
+    BINOPS.get(s).map(|x| x.0.clone()).ok_or(format!("Binop {} not found", s))
+  }
+  */
+  pub fn min_precedence() -> i32 {
+    i32::min_value()
+  }
+  pub fn get_precedence_from_token(op: &TokenType) -> Option<i32> {
+    use self::TokenType::*;
+    let s = match op {
+      Operator(op) => op,
+      Period => ".",
+      Pipe => "|",
+      Slash => "/",
+      LAngleBracket => "<",
+      RAngleBracket => ">",
+      _ => return None
+    };
+    let default = 10_000_000;
+    Some(BINOPS.get(s).map(|x| x.2.clone()).unwrap_or_else(|| {
+      println!("Warning: operator {} not defined", s);
+      default
+    }))
+  }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+pub struct PrefixOp {
+  sigil: Rc<String>
+}
+
+impl PrefixOp {
+  pub fn from_sigil(sigil: &str) -> PrefixOp {
+    PrefixOp { sigil: Rc::new(sigil.to_string()) }
+  }
+  pub fn sigil(&self) -> &Rc<String> {
+    &self.sigil
+  }
+  pub fn is_prefix(op: &str) -> bool {
+    PREFIX_OPS.get(op).is_some()
+  }
+  /*
+  pub fn get_type(&self) -> Result<Type, String> {
+    let s = self.sigil.as_str();
+    PREFIX_OPS.get(s).map(|x| x.0.clone()).ok_or(format!("Prefix op {} not found", s))
+  }
+  */
+}
+lazy_static! {
+  static ref PREFIX_OPS: HashMap<&'static str, (BuiltinTypeSpecifier, ())> = 
+    hashmap! {
+      "+" => (Func(bx!(Const(Int)),  bx!(Const(Int))), ()),
+      "-" => (Func(bx!(Const(Int)),  bx!(Const(Int))), ()),
+      "!" => (Func(bx!(Const(Bool)),  bx!(Const(Bool))), ()),
+    };
+}
+
+/* the second tuple member is a placeholder for when I want to make evaluation rules tied to the
+ * binop definition */
+lazy_static! {
+  static ref BINOPS: HashMap<&'static str, (BuiltinTypeSpecifier, (), i32)> =
+    hashmap! {
+      "+" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 10),
+      "-" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 10),
+      "*" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "/" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Float))))), (), 20),
+      "//" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20), //TODO change this to `quot`
+      "%" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "++" => (Func(bx!(Const(StringT)), bx!(Func(bx!(Const(StringT)), bx!(Const(StringT))))), (), 30),
+      "^" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "&" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "|" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      ">" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      ">=" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "<" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "<=" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "==" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "=" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+      "<=>" => (Func(bx!(Const(Nat)), bx!(Func(bx!(Const(Nat)), bx!(Const(Nat))))), (), 20),
+    };
+}

schala-lang/src/eval.rs

@@ -0,0 +1,482 @@
+
+use std::cell::RefCell;
+use std::rc::Rc;
+use std::fmt::Write;
+use std::io;
+
+use itertools::Itertools;
+
+use util::ScopeStack;
+use reduced_ast::{ReducedAST, Stmt, Expr, Lit, Func};
+use symbol_table::{SymbolSpec, Symbol, SymbolTable};
+
+pub struct State<'a> {
+  values: ScopeStack<'a, Rc<String>, ValueEntry>,
+  symbol_table_handle: Rc<RefCell<SymbolTable>>,
+}
+
+macro_rules! builtin_binding {
+  ($name:expr, $values:expr) => {
+    $values.insert(Rc::new(format!($name)), ValueEntry::Binding { constant: true, val: Node::Expr(Expr::Func(Func::BuiltIn(Rc::new(format!($name))))) });
+  }
+}
+
+//TODO add a more concise way of getting a new frame
+impl<'a> State<'a> {
+  pub fn new(symbol_table_handle: Rc<RefCell<SymbolTable>>) -> State<'a> {
+    let mut values = ScopeStack::new(Some(format!("global")));
+    builtin_binding!("print", values);
+    builtin_binding!("println", values);
+    builtin_binding!("getline", values);
+    State { values, symbol_table_handle }
+  }
+
+  pub fn debug_print(&self) -> String {
+    format!("Values: {:?}", self.values)
+  }
+}
+
+#[derive(Debug, Clone)]
+enum Node {
+  Expr(Expr),
+  PrimObject {
+    name: Rc<String>,
+    tag: usize,
+    items: Vec<Node>,
+  },
+  PrimTuple {
+    items: Vec<Node>
+  }
+}
+
+fn paren_wrapped_vec(terms: impl Iterator<Item=String>) -> String {
+  let mut buf = String::new();
+  write!(buf, "(").unwrap();
+  for term in terms.map(|e| Some(e)).intersperse(None) {
+    match term {
+      Some(e) => write!(buf, "{}", e).unwrap(),
+      None => write!(buf, ", ").unwrap(),
+    };
+  }
+  write!(buf, ")").unwrap();
+  buf
+}
+
+
+impl Node {
+  fn to_repl(&self) -> String {
+    match self {
+      Node::Expr(e) => e.to_repl(),
+      Node::PrimObject { name, items, .. } if items.len() == 0 => format!("{}", name),
+      Node::PrimObject { name, items, .. } => format!("{}{}", name, paren_wrapped_vec(items.iter().map(|x| x.to_repl()))),
+      Node::PrimTuple { items } => format!("{}", paren_wrapped_vec(items.iter().map(|x| x.to_repl()))),
+    }
+  }
+}
+
+#[derive(Debug)]
+enum ValueEntry {
+  Binding {
+    constant: bool,
+    val: /*FullyEvaluatedExpr*/ Node, //TODO make this use a subtype to represent fully evaluatedness
+  }
+}
+
+type EvalResult<T> = Result<T, String>;
+
+impl Expr {
+  fn to_node(self) -> Node {
+    Node::Expr(self)
+  }
+  fn to_repl(&self) -> String {
+    use self::Lit::*;
+    use self::Func::*;
+
+    match self {
+      Expr::Lit(ref l) => match l {
+        Nat(n) => format!("{}", n),
+        Int(i) => format!("{}", i),
+        Float(f) => format!("{}", f),
+        Bool(b) => format!("{}", b),
+        StringLit(s) => format!("\"{}\"", s),
+      },
+      Expr::Func(f) => match f {
+        BuiltIn(name) => format!("<built-in function '{}'>", name),
+        UserDefined { name: None, .. } => format!("<function>"),
+        UserDefined { name: Some(name), .. } => format!("<function '{}'>", name),
+      },
+      Expr::Constructor { 
+        type_name: _, name, tag, arity,
+      } => if *arity == 0 {
+        format!("{}", name)
+      } else {
+        format!("<data constructor '{}'>", name)
+      },
+      Expr::Tuple(exprs) => paren_wrapped_vec(exprs.iter().map(|x| x.to_repl())),
+      _ => format!("{:?}", self),
+    }
+  }
+}
+
+impl<'a> State<'a> {
+  pub fn evaluate(&mut self, ast: ReducedAST, repl: bool) -> Vec<Result<String, String>> {
+    let mut acc = vec![];
+
+    // handle prebindings
+    for statement in ast.0.iter() {
+      self.prebinding(statement);
+    }
+
+    for statement in ast.0 {
+      match self.statement(statement) {
+        Ok(Some(ref output)) if repl => acc.push(Ok(output.to_repl())),
+        Ok(_) => (),
+        Err(error) => {
+          acc.push(Err(format!("Runtime error: {}", error)));
+          return acc;
+        },
+      }
+    }
+    acc
+  }
+
+  fn prebinding(&mut self, stmt: &Stmt) {
+    match stmt {
+      Stmt::PreBinding { name, func } => {
+        let v_entry = ValueEntry::Binding { constant: true, val: Node::Expr(Expr::Func(func.clone())) };
+        self.values.insert(name.clone(), v_entry);
+      },
+      Stmt::Expr(_expr) => {
+        //TODO have this support things like nested function defs
+
+      },
+      _ => ()
+    }
+  }
+
+  fn statement(&mut self, stmt: Stmt) -> EvalResult<Option<Node>> {
+    match stmt {
+      Stmt::Binding { name, constant, expr } => {
+        let val = self.expression(Node::Expr(expr))?;
+        self.values.insert(name.clone(), ValueEntry::Binding { constant, val });
+        Ok(None)
+      },
+      Stmt::Expr(expr) => Ok(Some(self.expression(expr.to_node())?)),
+      Stmt::PreBinding {..} | Stmt::Noop => Ok(None),
+    }
+  }
+
+  fn block(&mut self, stmts: Vec<Stmt>) -> EvalResult<Node> {
+    let mut ret = None;
+    for stmt in stmts {
+      ret = self.statement(stmt)?;
+    }
+    Ok(ret.unwrap_or(Node::Expr(Expr::Unit)))
+  }
+
+  fn expression(&mut self, node: Node) -> EvalResult<Node> {
+    use self::Expr::*;
+    match node {
+      t @ Node::PrimTuple { .. } => Ok(t),
+      obj @ Node::PrimObject { .. } =>  Ok(obj),
+      Node::Expr(expr) => match expr {
+        literal @ Lit(_) => Ok(Node::Expr(literal)),
+        Call { box f, args } => match self.expression(Node::Expr(f))? {
+          Node::Expr(Constructor { type_name, name, tag, arity }) => self.apply_data_constructor(type_name, name, tag, arity, args),
+          Node::Expr(Func(f)) => self.apply_function(f, args),
+          other => return Err(format!("Tried to call {:?} which is not a function or data constructor", other)),
+        },
+        Val(v) => self.value(v),
+        Constructor { arity, ref name, tag, .. } if arity == 0 => Ok(Node::PrimObject { name: name.clone(), tag, items: vec![] }),
+        constructor @ Constructor { .. } => Ok(Node::Expr(constructor)),
+        func @ Func(_) => Ok(Node::Expr(func)),
+        Tuple(exprs) => {
+          let nodes = exprs.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
+          Ok(Node::PrimTuple { items: nodes })
+        },
+        Conditional { box cond, then_clause, else_clause } => self.conditional(cond, then_clause, else_clause),
+        Assign { box val, box expr } => {
+          let name = match val  {
+            Expr::Val(name) => name,
+            _ => return Err(format!("Trying to assign to a non-value")),
+          };
+
+          let constant = match self.values.lookup(&name) {
+            None => return Err(format!("{} is undefined", name)),
+            Some(ValueEntry::Binding { constant, .. }) => constant.clone(),
+          };
+          if constant {
+            return Err(format!("trying to update {}, a non-mutable binding", name));
+          }
+          let val = self.expression(Node::Expr(expr))?;
+          self.values.insert(name.clone(), ValueEntry::Binding { constant: false, val });
+          Ok(Node::Expr(Expr::Unit))
+        },
+        Unit => Ok(Node::Expr(Unit)),
+        CaseMatch { box cond, alternatives } => match self.expression(Node::Expr(cond))? {
+          Node::PrimObject { name, tag, items } => {
+            for alt in alternatives {
+              if alt.tag.map(|t| t == tag).unwrap_or(true) {
+                let mut inner_state = State {
+                  values: self.values.new_scope(None),
+                  symbol_table_handle: self.symbol_table_handle.clone(),
+                };
+                for (bound_var, val) in alt.bound_vars.iter().zip(items.iter()) {
+                  if let Some(bv) = bound_var.as_ref() {
+                    inner_state.values.insert(bv.clone(), ValueEntry::Binding { constant: true, val: val.clone() });
+                  }
+                }
+                return inner_state.block(alt.item)
+              }
+            }
+            return Err(format!("No matches found"));
+          },
+          Node::PrimTuple { .. } => Err(format!("Tuples don't work")),
+          Node::Expr(e) => Err(format!("Exprs don't work {:?}", e))
+        },
+        UnimplementedSigilValue => Err(format!("Sigil value eval not implemented"))
+      }
+    }
+  }
+
+  fn apply_data_constructor(&mut self, type_name: Rc<String>, name: Rc<String>, tag: usize, arity: usize, args: Vec<Expr>) -> EvalResult<Node> {
+    if arity != args.len() {
+      return Err(format!("Data constructor {} requires {} args", name, arity));
+    }
+
+    let evaled_args = args.into_iter().map(|expr| self.expression(Node::Expr(expr))).collect::<Result<Vec<Node>,_>>()?;
+    //let evaled_args = vec![];
+    Ok(Node::PrimObject {
+      name: name.clone(),
+      items: evaled_args,
+      tag 
+    })
+  }
+
+  fn apply_function(&mut self, f: Func, args: Vec<Expr>) -> EvalResult<Node> {
+    match f {
+      Func::BuiltIn(sigil) => Ok(Node::Expr(self.apply_builtin(sigil, args)?)),
+      Func::UserDefined { params, body, name } => {
+
+        if params.len() != args.len() {
+          return Err(format!("calling a {}-argument function with {} args", params.len(), args.len()))
+        }
+        let mut func_state = State {
+          values: self.values.new_scope(name.map(|n| format!("{}", n))),
+          symbol_table_handle: self.symbol_table_handle.clone(),
+        };
+        for (param, val) in params.into_iter().zip(args.into_iter()) {
+          let val = func_state.expression(Node::Expr(val))?;
+          func_state.values.insert(param, ValueEntry::Binding { constant: true, val });
+        }
+        // TODO figure out function return semantics
+        func_state.block(body)
+      }
+    }
+  }
+
+  fn apply_builtin(&mut self, name: Rc<String>, args: Vec<Expr>) -> EvalResult<Expr> {
+    use self::Expr::*;
+    use self::Lit::*;
+    let evaled_args: Result<Vec<Expr>, String> = args.into_iter().map(|arg| {
+      match self.expression(Node::Expr(arg)) {
+        Ok(Node::Expr(e)) => Ok(e),
+        Ok(Node::PrimTuple { .. }) => Err(format!("Trying to apply a builtin to a tuple")),
+        Ok(Node::PrimObject { .. }) => Err(format!("Trying to apply a builtin to a primitive object")),
+        Err(e) => Err(e)
+      }
+    }).collect();
+    let evaled_args = evaled_args?;
+
+    Ok(match (name.as_str(), evaled_args.as_slice()) {
+      /* binops */
+      ("+", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l + r)),
+      ("++", &[Lit(StringLit(ref s1)), Lit(StringLit(ref s2))]) => Lit(StringLit(Rc::new(format!("{}{}", s1, s2)))),
+      ("-", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l - r)),
+      ("*", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l * r)),
+      ("/", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Float((l as f64)/ (r as f64))),
+      ("//", &[Lit(Nat(l)), Lit(Nat(r))]) => if r == 0 {
+        return Err(format!("divide by zero"));
+      } else {
+        Lit(Nat(l / r))
+      },
+      ("%", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l % r)),
+      ("^", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l ^ r)),
+      ("&", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l & r)),
+      ("|", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Nat(l | r)),
+
+      /* comparisons */
+      ("==", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Bool(l == r)),
+      ("==", &[Lit(Int(l)), Lit(Int(r))]) => Lit(Bool(l == r)),
+      ("==", &[Lit(Float(l)), Lit(Float(r))]) => Lit(Bool(l == r)),
+      ("==", &[Lit(Bool(l)), Lit(Bool(r))]) => Lit(Bool(l == r)),
+      ("==", &[Lit(StringLit(ref l)), Lit(StringLit(ref r))]) => Lit(Bool(l == r)),
+
+      ("<", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Bool(l < r)),
+      ("<", &[Lit(Int(l)), Lit(Int(r))]) => Lit(Bool(l < r)),
+      ("<", &[Lit(Float(l)), Lit(Float(r))]) => Lit(Bool(l < r)),
+
+      ("<=", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Bool(l <= r)),
+      ("<=", &[Lit(Int(l)), Lit(Int(r))]) => Lit(Bool(l <= r)),
+      ("<=", &[Lit(Float(l)), Lit(Float(r))]) => Lit(Bool(l <= r)),
+
+      (">", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Bool(l > r)),
+      (">", &[Lit(Int(l)), Lit(Int(r))]) => Lit(Bool(l > r)),
+      (">", &[Lit(Float(l)), Lit(Float(r))]) => Lit(Bool(l > r)),
+
+      (">=", &[Lit(Nat(l)), Lit(Nat(r))]) => Lit(Bool(l >= r)),
+      (">=", &[Lit(Int(l)), Lit(Int(r))]) => Lit(Bool(l >= r)),
+      (">=", &[Lit(Float(l)), Lit(Float(r))]) => Lit(Bool(l >= r)),
+
+      /* prefix ops */
+      ("!", &[Lit(Bool(true))]) => Lit(Bool(false)),
+      ("!", &[Lit(Bool(false))]) => Lit(Bool(true)),
+      ("-", &[Lit(Nat(n))]) => Lit(Int(-1*(n as i64))),
+      ("-", &[Lit(Int(n))]) => Lit(Int(-1*(n as i64))),
+      ("+", &[Lit(Int(n))]) => Lit(Int(n)),
+      ("+", &[Lit(Nat(n))]) => Lit(Nat(n)),
+
+
+      /* builtin functions */
+      ("print", &[ref anything]) => {
+        print!("{}", anything.to_repl());
+        Expr::Unit
+      },
+      ("println", &[ref anything]) => {
+        println!("{}", anything.to_repl());
+        Expr::Unit
+      },
+      ("getline", &[]) => {
+        let mut buf = String::new();
+        io::stdin().read_line(&mut buf).expect("Error readling line in 'getline'");
+        Lit(StringLit(Rc::new(buf.trim().to_string())))
+      },
+      (x, args) => return Err(format!("bad or unimplemented builtin {:?} | {:?}", x, args)),
+    })
+  }
+
+  fn conditional(&mut self, cond: Expr, then_clause: Vec<Stmt>, else_clause: Vec<Stmt>) -> EvalResult<Node> {
+    let cond = self.expression(Node::Expr(cond))?;
+    Ok(match cond {
+      Node::Expr(Expr::Lit(Lit::Bool(true))) =>  self.block(then_clause)?,
+      Node::Expr(Expr::Lit(Lit::Bool(false))) => self.block(else_clause)?,
+      _ => return Err(format!("Conditional with non-boolean condition"))
+    })
+  }
+
+  fn value(&mut self, name: Rc<String>) -> EvalResult<Node> {
+    use self::ValueEntry::*;
+    use self::Func::*;
+    //TODO add a layer of indirection here to talk to the symbol table first, and only then look up
+    //in the values table
+
+    let symbol_table = self.symbol_table_handle.borrow();
+    let value = symbol_table.lookup_by_name(&name);
+    Ok(match value {
+      Some(Symbol { name, spec }) => match spec {
+        //TODO I'll need this type_name later to do a table lookup
+        SymbolSpec::DataConstructor { type_name: _type_name, type_args, .. } => {
+          if type_args.len() == 0 {
+            Node::PrimObject { name: name.clone(), tag: 0, items: vec![] }
+          } else {
+            return Err(format!("This data constructor thing not done"))
+          }
+        },
+        SymbolSpec::Func(_) => match self.values.lookup(&name) {
+          Some(Binding { val: Node::Expr(Expr::Func(UserDefined { name, params, body })), .. }) => {
+            Node::Expr(Expr::Func(UserDefined { name: name.clone(), params: params.clone(), body: body.clone() }))
+          },
+          _ => unreachable!(),
+        },
+      },
+      /* see if it's an ordinary variable TODO make variables go in symbol table */
+      None => match self.values.lookup(&name) {
+        Some(Binding { val, .. }) => val.clone(),
+        None => return Err(format!("Couldn't find value {}", name)),
+      }
+    })
+  }
+}
+
+#[cfg(test)]
+mod eval_tests {
+  use std::cell::RefCell;
+  use std::rc::Rc;
+  use symbol_table::SymbolTable;
+  use tokenizing::tokenize;
+  use parsing::parse;
+  use eval::State;
+
+  macro_rules! all_output {
+    ($string:expr) => {
+      {
+        let symbol_table = Rc::new(RefCell::new(SymbolTable::new()));
+        let mut state = State::new(symbol_table);
+        let ast = parse(tokenize($string)).0.unwrap();
+        state.symbol_table_handle.borrow_mut().add_top_level_symbols(&ast).unwrap();
+        let reduced = ast.reduce(&state.symbol_table_handle.borrow());
+        let all_output = state.evaluate(reduced, true);
+        all_output
+      }
+    }
+  }
+
+  macro_rules! fresh_env {
+    ($string:expr, $correct:expr) => {
+      {
+        let all_output = all_output!($string);
+        let ref output = all_output.last().unwrap();
+        assert_eq!(**output, Ok($correct.to_string()));
+      }
+    }
+  }
+
+  #[test]
+  fn test_basic_eval() {
+    fresh_env!("1 + 2", "3");
+    fresh_env!("let mut a = 1; a = 2", "Unit");
+    fresh_env!("let mut a = 1; a = 2; a", "2");
+    fresh_env!(r#"("a", 1 + 2)"#, r#"("a", 3)"#);
+  }
+
+  #[test]
+  fn function_eval() {
+    fresh_env!("fn oi(x) { x + 1 }; oi(4)", "5");
+    fresh_env!("fn oi(x) { x + 1 }; oi(1+2)", "4");
+  }
+
+  #[test]
+  fn scopes() {
+    let scope_ok = r#"
+    let a = 20
+    fn haha() {
+      let a = 10
+      a
+    }
+    haha()
+    "#;
+    fresh_env!(scope_ok, "10");
+    let scope_ok = r#"
+    let a = 20
+    fn haha() {
+      let a = 10
+      a
+    }
+    a
+    "#;
+    fresh_env!(scope_ok, "20");
+  }
+
+  #[test]
+  fn basic_patterns() {
+    let source = r#"
+type Option<T> = Some(T) | None
+let x = Some(9); if x is Some(q) then { q } else { 0 }"#;
+    fresh_env!(source, "9");
+
+    let source = r#"
+type Option<T> = Some(T) | None
+let x = None; if x is Some(q) then { q } else { 0 }"#;
+    fresh_env!(source, "0");
+  }
+}

schala-lang/src/lib.rs

@@ -0,0 +1,148 @@
+#![feature(trace_macros)]
+#![feature(slice_patterns, box_patterns, box_syntax)]
+extern crate itertools;
+#[macro_use]
+extern crate lazy_static;
+#[macro_use]
+extern crate maplit;
+#[macro_use]
+extern crate schala_repl;
+#[macro_use]
+extern crate schala_codegen;
+
+use std::cell::RefCell;
+use std::rc::Rc;
+
+use itertools::Itertools;
+use schala_repl::{ProgrammingLanguageInterface, EvalOptions, TraceArtifact, UnfinishedComputation, FinishedComputation};
+
+macro_rules! bx {
+  ($e:expr) => { Box::new($e) }
+}
+
+mod util;
+mod builtin;
+mod tokenizing;
+mod ast;
+mod parsing;
+mod symbol_table;
+mod typechecking;
+mod reduced_ast;
+mod eval;
+
+//trace_macros!(true);
+#[derive(ProgrammingLanguageInterface)]
+#[LanguageName = "Schala"]
+#[SourceFileExtension = "schala"]
+#[PipelineSteps(tokenizing, parsing(compact,expanded,trace), symbol_table, typechecking, ast_reducing, eval)]
+pub struct Schala {
+  state: eval::State<'static>,
+  symbol_table: Rc<RefCell<symbol_table::SymbolTable>>,
+  type_context: typechecking::TypeContext<'static>,
+}
+
+
+impl Schala {
+  fn new_blank_env() -> Schala {
+    let symbols = Rc::new(RefCell::new(symbol_table::SymbolTable::new()));
+    Schala {
+      symbol_table: symbols.clone(),
+      type_context: typechecking::TypeContext::new(symbols.clone()),
+      state: eval::State::new(symbols),
+    }
+  }
+
+  pub fn new() -> Schala {
+    let prelude = r#"
+type Option<T> = Some(T) | None
+type Color = Red | Green | Blue
+type Ord = LT | EQ | GT
+    "#;
+    let mut s = Schala::new_blank_env();
+    s.execute_pipeline(prelude, &EvalOptions::default());
+    s
+  }
+}
+
+fn tokenizing(_handle: &mut Schala, input: &str, comp: Option<&mut UnfinishedComputation>) -> Result<Vec<tokenizing::Token>, String> {
+  let tokens = tokenizing::tokenize(input);
+  comp.map(|comp| {
+    let token_string = tokens.iter().map(|t| format!("{:?}<L:{},C:{}>", t.token_type, t.offset.0, t.offset.1)).join(", ");
+    comp.add_artifact(TraceArtifact::new("tokens", token_string));
+  });
+
+  let errors: Vec<String> = tokens.iter().filter_map(|t| t.get_error()).collect();
+  if errors.len() == 0 {
+    Ok(tokens)
+  } else {
+    Err(format!("{:?}", errors))
+  }
+}
+
+fn parsing(_handle: &mut Schala, input: Vec<tokenizing::Token>, comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+
+  let (ast, trace) = parsing::parse(input);
+  comp.map(|comp| {
+    //TODO need to control which of these debug stages get added
+    let opt = comp.cur_debug_options.get(0).map(|s| s.clone());
+    match opt {
+      None => comp.add_artifact(TraceArtifact::new("ast", format!("{:?}", ast))),
+      Some(ref s) if s == "compact" => comp.add_artifact(TraceArtifact::new("ast", format!("{:?}", ast))),
+      Some(ref s) if s == "expanded" => comp.add_artifact(TraceArtifact::new("ast", format!("{:#?}", ast))),
+      Some(ref s) if s == "trace" => comp.add_artifact(TraceArtifact::new_parse_trace(trace)),
+      Some(ref x) => println!("Bad parsing debug option: {}", x),
+    };
+  });
+  ast.map_err(|err| err.msg)
+}
+
+fn symbol_table(handle: &mut Schala, input: ast::AST, comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+  let add = handle.symbol_table.borrow_mut().add_top_level_symbols(&input);
+  match add {
+    Ok(()) => {
+      let artifact = TraceArtifact::new("symbol_table", handle.symbol_table.borrow().debug_symbol_table());
+      comp.map(|comp| comp.add_artifact(artifact));
+      Ok(input)
+    },
+    Err(msg) => Err(msg)
+  }
+}
+
+fn typechecking(handle: &mut Schala, input: ast::AST, comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+  match handle.type_context.type_check_ast(&input) {
+    Ok(ty) => {
+      comp.map(|c| {
+        c.add_artifact(TraceArtifact::new("type_table", format!("{}", handle.type_context.debug_types())));
+        c.add_artifact(TraceArtifact::new("type_check", format!("{:?}", ty)));
+      });
+      Ok(input)
+    },
+    Err(msg) => {
+      comp.map(|comp| {
+        comp.add_artifact(TraceArtifact::new("type_table", format!("{}", handle.type_context.debug_types())));
+        comp.add_artifact(TraceArtifact::new("type_check", format!("Type error: {:?}", msg)));
+      });
+      Ok(input)
+    }
+  }
+}
+
+fn ast_reducing(handle: &mut Schala, input: ast::AST, comp: Option<&mut UnfinishedComputation>) -> Result<reduced_ast::ReducedAST, String> {
+  let ref symbol_table = handle.symbol_table.borrow();
+  let output = input.reduce(symbol_table);
+  comp.map(|comp| comp.add_artifact(TraceArtifact::new("ast_reducing", format!("{:?}", output))));
+  Ok(output)
+}
+
+fn eval(handle: &mut Schala, input: reduced_ast::ReducedAST, comp: Option<&mut UnfinishedComputation>) -> Result<String, String> {
+  comp.map(|comp| comp.add_artifact(TraceArtifact::new("value_state", handle.state.debug_print())));
+  let evaluation_outputs = handle.state.evaluate(input, true);
+  let text_output: Result<Vec<String>, String> = evaluation_outputs
+    .into_iter()
+    .collect();
+
+  let eval_output: Result<String, String> = text_output
+    .map(|v| { v.into_iter().intersperse(format!("\n")).collect() });
+  eval_output
+}
+

schala-lang/src/reduced_ast.rs

@@ -0,0 +1,282 @@
+use std::rc::Rc;
+
+use ast::{AST, Statement, Expression, Declaration, Discriminator, IfExpressionBody, Pattern, PatternLiteral, Guard, HalfExpr};
+use symbol_table::{Symbol, SymbolSpec, SymbolTable};
+use builtin::{BinOp, PrefixOp};
+
+#[derive(Debug)]
+pub struct ReducedAST(pub Vec<Stmt>);
+
+#[derive(Debug, Clone)]
+pub enum Stmt {
+  PreBinding {
+    name: Rc<String>,
+    func: Func,
+  },
+  Binding {
+    name: Rc<String>,
+    constant: bool,
+    expr: Expr,
+  },
+  Expr(Expr),
+  Noop,
+}
+
+#[derive(Debug, Clone)]
+pub enum Expr {
+  Unit,
+  Lit(Lit),
+  Tuple(Vec<Expr>),
+  Func(Func),
+  Val(Rc<String>),
+  Constructor {
+    type_name: Rc<String>,
+    name: Rc<String>,
+    tag: usize,
+    arity: usize,
+  },
+  Call {
+    f: Box<Expr>,
+    args: Vec<Expr>,
+  },
+  Assign {
+    val: Box<Expr>,
+    expr: Box<Expr>,
+  },
+  Conditional {
+    cond: Box<Expr>,
+    then_clause: Vec<Stmt>,
+    else_clause: Vec<Stmt>,
+  },
+  CaseMatch {
+    cond: Box<Expr>,
+    alternatives: Vec<Alternative>
+  },
+  UnimplementedSigilValue
+}
+
+#[derive(Debug, Clone)]
+pub struct Alternative {
+  pub tag: Option<usize>,
+  pub guards: Vec<Expr>,
+  pub bound_vars: Vec<Option<Rc<String>>>, //order here is iconic to order in a tuple-like type, None is equivalent to ignored
+  pub item: Vec<Stmt>,
+}
+
+#[derive(Debug, Clone)]
+pub enum Lit {
+  Nat(u64),
+  Int(i64),
+  Float(f64),
+  Bool(bool),
+  StringLit(Rc<String>),
+}
+
+#[derive(Debug, Clone)]
+pub enum Func {
+  BuiltIn(Rc<String>),
+  UserDefined {
+    name: Option<Rc<String>>,
+    params: Vec<Rc<String>>,
+    body: Vec<Stmt>,
+  }
+}
+
+impl AST {
+  pub fn reduce(&self, symbol_table: &SymbolTable) -> ReducedAST {
+    let mut output = vec![];
+    for statement in self.0.iter() {
+      output.push(statement.reduce(symbol_table));
+    }
+    ReducedAST(output)
+  }
+}
+
+impl Statement {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Stmt { 
+    use ast::Statement::*;
+    match self {
+      ExpressionStatement(expr) => Stmt::Expr(expr.reduce(symbol_table)),
+      Declaration(decl) => decl.reduce(symbol_table),
+    }
+  }
+}
+
+impl Expression {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Expr {
+    use ast::ExpressionType::*;
+    let ref input = self.0;
+    match input {
+      NatLiteral(n) => Expr::Lit(Lit::Nat(*n)),
+      FloatLiteral(f) => Expr::Lit(Lit::Float(*f)),
+      StringLiteral(s) => Expr::Lit(Lit::StringLit(s.clone())),
+      BoolLiteral(b) => Expr::Lit(Lit::Bool(*b)),
+      BinExp(binop, lhs, rhs) => binop.reduce(symbol_table, lhs, rhs),
+      PrefixExp(op, arg) => op.reduce(symbol_table, arg),
+      Value(name) => match symbol_table.lookup_by_name(name) {
+        Some(Symbol { spec: SymbolSpec::DataConstructor { index, type_args, type_name}, .. }) => Expr::Constructor {
+          type_name: type_name.clone(),
+          name: name.clone(),
+          tag: index.clone(),
+          arity: type_args.len(),
+        },
+        _ => Expr::Val(name.clone()),
+      },
+      Call { f, arguments } => Expr::Call {
+        f: Box::new(f.reduce(symbol_table)),
+        args: arguments.iter().map(|arg| arg.reduce(symbol_table)).collect(),
+      },
+      TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| e.reduce(symbol_table)).collect()),
+      IfExpression { discriminator, body } => reduce_if_expression(discriminator, body, symbol_table),
+      _ => Expr::UnimplementedSigilValue,
+    }
+  }
+}
+
+fn reduce_if_expression(discriminator: &Discriminator, body: &IfExpressionBody, symbol_table: &SymbolTable) -> Expr {
+  let cond = Box::new(match *discriminator {
+    Discriminator::Simple(ref expr) => expr.reduce(symbol_table),
+    Discriminator::BinOp(ref expr, ref binop) => {
+      panic!()
+    }
+  });
+  match *body {
+    IfExpressionBody::SimpleConditional(ref then_clause, ref else_clause) => {
+      let then_clause = then_clause.iter().map(|expr| expr.reduce(symbol_table)).collect();
+      let else_clause = match else_clause {
+        None => vec![],
+        Some(stmts) => stmts.iter().map(|expr| expr.reduce(symbol_table)).collect(),
+      };
+      Expr::Conditional { cond, then_clause, else_clause }
+    },
+    IfExpressionBody::SimplePatternMatch(ref pat, ref then_clause, ref else_clause) => {
+      let then_clause = then_clause.iter().map(|expr| expr.reduce(symbol_table)).collect();
+      let else_clause = match else_clause {
+        None => vec![],
+        Some(stmts) => stmts.iter().map(|expr| expr.reduce(symbol_table)).collect(),
+      };
+
+      let alternatives = vec![
+        pat.to_alternative(then_clause, symbol_table),
+        Alternative {
+          tag: None,
+          guards: vec![],
+          bound_vars: vec![],
+          item: else_clause,
+        },
+      ];
+
+      Expr::CaseMatch {
+        cond,
+        alternatives,
+      }
+    },
+    IfExpressionBody::GuardList(ref guard_arms) => {
+      let alternatives = guard_arms.iter().map(|arm| match arm.guard {
+        Guard::Pat(ref p) =>  {
+          let item = arm.body.iter().map(|expr| expr.reduce(symbol_table)).collect();
+          p.to_alternative(item, symbol_table)
+        },
+        Guard::HalfExpr(HalfExpr { op: _, expr: _ }) => {
+          unimplemented!()
+        }
+      }).collect();
+      Expr::CaseMatch { cond, alternatives }
+    }
+  }
+}
+
+impl Pattern {
+  fn to_alternative(&self, item: Vec<Stmt>, symbol_table: &SymbolTable) -> Alternative {
+    use self::Pattern::*;
+    match self {
+      TupleStruct(name, subpatterns) => {
+        let symbol = symbol_table.values.get(name).expect(&format!("Symbol {} not found", name));
+        let tag = match symbol.spec {
+          SymbolSpec::DataConstructor { index, .. } => index.clone(),
+          _ => panic!("Bad symbol"),
+        };
+
+        /*
+        let guards = patterns.iter().map(|p| match p {
+
+
+        });
+        */
+        let guards = unimplemented!();
+
+        let bound_vars = subpatterns.iter().map(|p| match p {
+          Literal(PatternLiteral::VarPattern(var)) => Some(var.clone()),
+          Ignored => None,
+          _ => None,
+        }).collect();
+        Alternative {
+          tag: Some(tag),
+          guards,
+          bound_vars,
+          item,
+        }
+      },
+      TuplePattern(_items) => {
+        unimplemented!()
+      },
+      Record(_name, _pairs) => {
+        unimplemented!()
+      },
+      Ignored => unimplemented!(),
+      /* "a constant appearing in a pattern can easily be eliminated by replacing it with a variable
+       * and adding a guard to the equation instead" -  Implementation of Functional Programming
+       * Languages Simon Peyton-Jones, p. 58 */
+      Literal(lit) => match lit {
+        PatternLiteral::NumPattern { neg, num } => unimplemented!(),
+        PatternLiteral::StringPattern(_s) => unimplemented!(),
+        PatternLiteral::BoolPattern(_b) => unimplemented!(),
+        PatternLiteral::VarPattern(_var) => unimplemented!(),
+      },
+    }
+  }
+}
+
+impl Declaration {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Stmt {
+    use self::Declaration::*;
+    use ::ast::Signature;
+    match self {
+      Binding {name, constant, expr } => Stmt::Binding { name: name.clone(), constant: *constant, expr: expr.reduce(symbol_table) },
+      FuncDecl(Signature { name, params, .. }, statements) => Stmt::PreBinding {
+        name: name.clone(),
+        func: Func::UserDefined {
+          name: Some(name.clone()),
+          params: params.iter().map(|param| param.0.clone()).collect(),
+          body: statements.iter().map(|stmt| stmt.reduce(symbol_table)).collect(),
+        }
+      },
+      TypeDecl { .. } => Stmt::Noop,
+      TypeAlias(_, _) => Stmt::Noop,
+      Interface { .. } => Stmt::Noop,
+      Impl { .. } => Stmt::Expr(Expr::UnimplementedSigilValue),
+      _ => Stmt::Expr(Expr::UnimplementedSigilValue)
+    }
+  }
+}
+
+impl BinOp {
+  fn reduce(&self, symbol_table: &SymbolTable, lhs: &Box<Expression>, rhs: &Box<Expression>) -> Expr {
+    if **self.sigil() == "=" {
+      Expr::Assign {
+        val: Box::new(lhs.reduce(symbol_table)),
+        expr: Box::new(rhs.reduce(symbol_table)),
+      }
+    } else {
+      let f = Box::new(Expr::Func(Func::BuiltIn(self.sigil().clone())));
+      Expr::Call { f, args: vec![lhs.reduce(symbol_table), rhs.reduce(symbol_table)]}
+    }
+  }
+}
+
+impl PrefixOp {
+  fn reduce(&self, symbol_table: &SymbolTable, arg: &Box<Expression>) -> Expr {
+    let f = Box::new(Expr::Func(Func::BuiltIn(self.sigil().clone())));
+    Expr::Call { f, args: vec![arg.reduce(symbol_table)]}
+  }
+}

schala-lang/src/symbol_table.rs

@@ -0,0 +1,131 @@
+use std::collections::HashMap;
+use std::rc::Rc;
+use std::fmt;
+use std::fmt::Write;
+
+use ast;
+use typechecking::TypeName;
+
+//cf. p. 150 or so of Language Implementation Patterns
+pub struct SymbolTable {
+  pub values: HashMap<Rc<String>, Symbol> //TODO this will eventually have real type information
+}
+
+//TODO add various types of lookups here, maybe multiple hash tables internally? also make values
+//non-public
+impl SymbolTable {
+  pub fn new() -> SymbolTable {
+    SymbolTable { values: HashMap::new() }
+  }
+
+  pub fn lookup_by_name(&self, name: &Rc<String>) -> Option<&Symbol> {
+    self.values.get(name)
+  }
+}
+
+#[derive(Debug)]
+pub struct Symbol {
+  pub name: Rc<String>,
+  pub spec: SymbolSpec,
+}
+
+impl fmt::Display for Symbol {
+  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    write!(f, "<Name: {}, Spec: {}>", self.name, self.spec)
+  }
+}
+
+#[derive(Debug)]
+pub enum SymbolSpec {
+  Func(Vec<TypeName>),
+  DataConstructor {
+    index: usize,
+    type_name: Rc<String>,
+    type_args: Vec<Rc<String>>,
+  },
+}
+
+impl fmt::Display for SymbolSpec {
+  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    use self::SymbolSpec::*;
+    match self {
+      Func(type_names) => write!(f, "Func({:?})", type_names),
+      DataConstructor { index, type_name, type_args } => write!(f, "DataConstructor({})({:?} -> {})", index, type_args, type_name),
+    }
+  }
+}
+
+impl SymbolTable {
+  /* note: this adds names for *forward reference* but doesn't actually create any types. solve that problem
+   * later */
+  pub fn add_top_level_symbols(&mut self, ast: &ast::AST) -> Result<(), String> {
+    use self::ast::{Statement, TypeName, Variant, TypeSingletonName, TypeBody};
+    use self::ast::Declaration::*;
+    for statement in ast.0.iter() {
+      if let Statement::Declaration(decl) = statement {
+        match decl {
+          FuncSig(signature) | FuncDecl(signature, _) => {
+            let mut ch: char = 'a';
+            let mut types = vec![];
+            for param in signature.params.iter() {
+              match param {
+                (_, Some(_ty)) => {
+                  //TODO eventually handle this case different
+                  types.push(Rc::new(format!("{}", ch)));
+                  ch = ((ch as u8) + 1) as char;
+                },
+                (_, None) => {
+                  types.push(Rc::new(format!("{}", ch)));
+                  ch = ((ch as u8) + 1) as char;
+                }
+              }
+            }
+            let spec = SymbolSpec::Func(types);
+            self.values.insert(
+              signature.name.clone(),
+              Symbol { name: signature.name.clone(), spec }
+              );
+          },
+          //TODO figure out why _params isn't being used here
+          TypeDecl { name: TypeSingletonName { name, params: _params}, body: TypeBody(variants), mutable: _mutable, } => {
+            for (index, var) in variants.iter().enumerate() {
+              match var {
+                Variant::UnitStruct(variant_name) => {
+                  let spec = SymbolSpec::DataConstructor {
+                    index,
+                    type_name: name.clone(),
+                    type_args: vec![],
+                  };
+                  self.values.insert(variant_name.clone(), Symbol { name: variant_name.clone(), spec });
+                },
+                Variant::TupleStruct(variant_name, tuple_members) => {
+                  let type_args = tuple_members.iter().map(|type_name| match type_name {
+                    TypeName::Singleton(TypeSingletonName { name, ..}) => name.clone(),
+                    TypeName::Tuple(_) => unimplemented!(),
+                  }).collect();
+                  let spec = SymbolSpec::DataConstructor {
+                    index,
+                    type_name: name.clone(),
+                    type_args
+                  };
+                  let symbol = Symbol { name: variant_name.clone(), spec };
+                  self.values.insert(variant_name.clone(), symbol);
+                },
+                e => return Err(format!("{:?} not supported in typing yet", e)),
+              }
+            }
+          },
+          _ => ()
+        }
+      }
+    }
+    Ok(())
+  }
+  pub fn debug_symbol_table(&self) -> String {
+    let mut output = format!("Symbol table\n");
+    for (name, sym) in &self.values {
+      write!(output, "{} -> {}\n", name, sym).unwrap();
+    }
+    output
+  }
+}

schala-lang/src/tokenizing.rs

@@ -5,17 +5,17 @@ use std::iter::{Iterator, Peekable};
 use std::fmt;
 
 #[derive(Debug, PartialEq, Clone)]
-pub enum TokenKind {
+pub enum TokenType {
   Newline, Semicolon,
 
   LParen, RParen,
   LSquareBracket, RSquareBracket,
   LAngleBracket, RAngleBracket,
   LCurlyBrace, RCurlyBrace,
-  Pipe, Backslash,
+  Pipe,
 
   Comma, Period, Colon, Underscore,
-  Slash, Equals,
+  Slash,
 
   Operator(Rc<String>),
   DigitGroup(Rc<String>), HexLiteral(Rc<String>), BinNumberSigil,
@@ -27,9 +27,9 @@ pub enum TokenKind {
 
   Error(String),
 }
-use self::TokenKind::*;
+use self::TokenType::*;
 
-impl fmt::Display for TokenKind {
+impl fmt::Display for TokenType {
   fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
     match self {
       &Operator(ref s) => write!(f, "Operator({})", **s),
@@ -87,24 +87,19 @@ lazy_static! {
 
 #[derive(Debug, Clone)]
 pub struct Token {
-  pub kind: TokenKind,
-  pub line_num: usize,
-  pub char_num: usize
+  pub token_type: TokenType,
+  pub offset: (usize, usize),
 }
 
 impl Token {
   pub fn get_error(&self) -> Option<String> {
-    match self.kind {
-      TokenKind::Error(ref s) => Some(s.clone()),
+    match self.token_type {
+      TokenType::Error(ref s) => Some(s.clone()),
       _ => None,
     }
   }
   pub fn to_string_with_metadata(&self) -> String {
-    format!("{}(L:{},c:{})", self.kind, self.line_num, self.char_num)
-  }
-
-  pub fn get_kind(&self) -> TokenKind {
-    self.kind.clone()
+    format!("{}(L:{},c:{})", self.token_type, self.offset.0, self.offset.1)
   }
 }
 
@@ -118,15 +113,15 @@ type CharData = (usize, usize, char);
 pub fn tokenize(input: &str) -> Vec<Token> {
   let mut tokens: Vec<Token> = Vec::new();
 
-  let mut input = input.lines().enumerate()
+  let mut input  = input.lines().enumerate()
       .intersperse((0, "\n"))
       .flat_map(|(line_idx, ref line)| {
           line.chars().enumerate().map(move |(ch_idx, ch)| (line_idx, ch_idx, ch))
       })
       .peekable();
 
-  while let Some((line_num, char_num, c)) = input.next() {
-    let cur_tok_kind = match c {
+  while let Some((line_idx, ch_idx, c)) = input.next() {
+    let cur_tok_type = match c {
       '/' => match input.peek().map(|t| t.2) {
         Some('/') => {
           while let Some((_, _, c)) = input.next() {
@@ -162,18 +157,17 @@ pub fn tokenize(input: &str) -> Vec<Token> {
       '{' => LCurlyBrace, '}' => RCurlyBrace,
       '[' => LSquareBracket, ']' => RSquareBracket,
       '"' => handle_quote(&mut input),
-      '\\' => Backslash,
       c if c.is_digit(10) => handle_digit(c, &mut input),
-      c if c.is_alphabetic() || c == '_' => handle_alphabetic(c, &mut input),
+      c if c.is_alphabetic() || c == '_' => handle_alphabetic(c, &mut input), //TODO I'll probably have to rewrite this if I care about types being uppercase, also type parameterization
       c if is_operator(&c) => handle_operator(c, &mut input),
       unknown => Error(format!("Unexpected character: {}", unknown)),
     };
-    tokens.push(Token { kind: cur_tok_kind, line_num, char_num });
+    tokens.push(Token { token_type: cur_tok_type, offset: (line_idx, ch_idx) });
   }
   tokens
 }
 
-fn handle_digit(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
+fn handle_digit(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenType {
   if c == '0' && input.peek().map_or(false, |&(_, _, c)| { c == 'x' }) {
     input.next();
     let rest: String = input.peeking_take_while(|&(_, _, ref c)| c.is_digit(16) || *c == '_').map(|(_, _, c)| { c }).collect();
@@ -188,7 +182,7 @@ fn handle_digit(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) ->
   }
 }
 
-fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
+fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenType {
   let mut buf = String::new();
   loop {
     match input.next().map(|(_, _, c)| { c }) {
@@ -207,22 +201,22 @@ fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind
         }
       },
       Some(c) => buf.push(c),
-      None => return TokenKind::Error(format!("Unclosed string")),
+      None => return TokenType::Error(format!("Unclosed string")),
     }
   }
-  TokenKind::StrLiteral(Rc::new(buf))
+  TokenType::StrLiteral(Rc::new(buf))
 }
 
-fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
+fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenType {
   let mut buf = String::new();
   buf.push(c);
   if c == '_' && input.peek().map(|&(_, _, c)| { !c.is_alphabetic() }).unwrap_or(true) {
-    return TokenKind::Underscore
+    return TokenType::Underscore
   }
 
   loop {
     match input.peek().map(|&(_, _, c)| { c }) {
-      Some(c) if c.is_alphanumeric() || c == '_' => {
+      Some(c) if c.is_alphanumeric() => {
         input.next();
         buf.push(c);
       },
@@ -231,14 +225,14 @@ fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>
   }
 
   match KEYWORDS.get(buf.as_str()) {
-    Some(kw) => TokenKind::Keyword(*kw),
-    None => TokenKind::Identifier(Rc::new(buf)),
+    Some(kw) => TokenType::Keyword(*kw),
+    None => TokenType::Identifier(Rc::new(buf)),
   }
 }
 
-fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
+fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenType {
   match c {
-    '<' | '>' | '|' | '.' | '=' => {
+    '<' | '>' | '|' | '.' => {
       let ref next = input.peek().map(|&(_, _, c)| { c });
       if !next.map(|n| { is_operator(&n) }).unwrap_or(false) {
         return match c {
@@ -246,7 +240,6 @@ fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>)
           '>' => RAngleBracket,
           '|' => Pipe,
           '.' => Period,
-          '=' => Equals,
           _ => unreachable!(),
         }
       }
@@ -282,7 +275,7 @@ fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>)
       }
     }
   }
-  TokenKind::Operator(Rc::new(buf))
+  TokenType::Operator(Rc::new(buf))
 }
 
 #[cfg(test)]
@@ -297,29 +290,26 @@ mod schala_tokenizer_tests {
   #[test]
   fn tokens() {
     let a = tokenize("let a: A<B> = c ++ d");
-    let token_kinds: Vec<TokenKind> = a.into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![Keyword(Let), ident!("a"), Colon, ident!("A"),
-      LAngleBracket, ident!("B"), RAngleBracket, Equals, ident!("c"), op!("++"), ident!("d")]);
+    let token_types: Vec<TokenType> = a.into_iter().map(move |t| t.token_type).collect();
+    assert_eq!(token_types, vec![Keyword(Let), ident!("a"), Colon, ident!("A"),
+      LAngleBracket, ident!("B"), RAngleBracket, op!("="), ident!("c"), op!("++"), ident!("d")]);
   }
 
   #[test]
   fn underscores() {
-    let token_kinds: Vec<TokenKind> = tokenize("4_8").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("4"), Underscore, digit!("8")]);
-
-    let token_kinds2: Vec<TokenKind> = tokenize("aba_yo").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds2, vec![ident!("aba_yo")]);
+    let token_types: Vec<TokenType> = tokenize("4_8").into_iter().map(move |t| t.token_type).collect();
+    assert_eq!(token_types, vec![digit!("4"), Underscore, digit!("8")]);
   }
 
   #[test]
   fn comments() {
-    let token_kinds: Vec<TokenKind> = tokenize("1  + /* hella /* bro */ */ 2").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("1"), op!("+"), digit!("2")]);
+    let token_types: Vec<TokenType> = tokenize("1  + /* hella /* bro */ */ 2").into_iter().map(move |t| t.token_type).collect();
+    assert_eq!(token_types, vec![digit!("1"), op!("+"), digit!("2")]);
   }
 
   #[test]
   fn backtick_operators() {
-    let token_kinds: Vec<TokenKind> = tokenize("1 `plus` 2").into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![digit!("1"), op!("plus"), digit!("2")]);
+    let token_types: Vec<TokenType> = tokenize("1 `plus` 2").into_iter().map(move |t| t.token_type).collect();
+    assert_eq!(token_types, vec![digit!("1"), op!("plus"), digit!("2")]);
   }
 }

schala-lang/src/typechecking.rs

@@ -0,0 +1,493 @@
+use std::cell::RefCell;
+use std::rc::Rc;
+use std::collections::HashMap;
+use std::fmt;
+use std::fmt::Write;
+/*
+use std::collections::hash_set::Union;
+use std::iter::Iterator;
+use itertools::Itertools;
+*/
+
+use ast;
+use util::ScopeStack;
+use symbol_table::{SymbolSpec, SymbolTable};
+
+pub type TypeName = Rc<String>;
+type TypeResult<T> = Result<T, String>;
+
+#[derive(Debug, PartialEq, Clone)]
+enum Type {
+  Const(TConst),
+  Var(TypeName),
+  Func(Vec<Type>),
+}
+
+#[derive(Debug, PartialEq, Clone)]
+enum TConst {
+  Unit,
+  Nat,
+  StringT,
+  //Custom(String)
+}
+
+#[derive(Debug, PartialEq, Clone)]
+struct Scheme {
+  names: Vec<TypeName>,
+  ty: Type,
+}
+
+impl fmt::Display for Scheme {
+  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    write!(f, "∀{:?} . {:?}", self.names, self.ty)
+  }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+struct Substitution(HashMap<TypeName, Type>);
+impl Substitution {
+  fn empty() -> Substitution {
+    Substitution(HashMap::new())
+  }
+}
+
+#[derive(Debug, PartialEq, Clone)]
+struct TypeEnv(HashMap<TypeName, Scheme>);
+
+impl TypeEnv {
+  fn default() -> TypeEnv {
+    TypeEnv(HashMap::new())
+  }
+
+  fn populate_from_symbols(&mut self, symbol_table: &SymbolTable) {
+    for (name, symbol) in symbol_table.values.iter() {
+      if let SymbolSpec::Func(ref type_names) = symbol.spec {
+        let mut ch: char = 'a';
+        let mut names = vec![];
+        for _ in type_names.iter() {
+          names.push(Rc::new(format!("{}", ch)));
+          ch = ((ch as u8) + 1) as char;
+        }
+
+        let sigma = Scheme {
+          names: names.clone(),
+          ty: Type::Func(names.into_iter().map(|n| Type::Var(n)).collect())
+        };
+        self.0.insert(name.clone(), sigma);
+      }
+    }
+  }
+}
+
+pub struct TypeContext<'a> {
+  values: ScopeStack<'a, TypeName, Type>,
+  symbol_table_handle: Rc<RefCell<SymbolTable>>,
+  global_env: TypeEnv
+}
+
+impl<'a> TypeContext<'a> {
+  pub fn new(symbol_table_handle: Rc<RefCell<SymbolTable>>) -> TypeContext<'static> {
+    TypeContext { values: ScopeStack::new(None), global_env: TypeEnv::default(), symbol_table_handle }
+  }
+
+  pub fn debug_types(&self) -> String {
+    let mut output = format!("Type environment\n");
+    for (name, scheme) in &self.global_env.0 {
+      write!(output, "{} -> {}\n", name, scheme).unwrap();
+    }
+    output
+  }
+
+  pub fn type_check_ast(&mut self, input: &ast::AST) -> Result<String, String> {
+    let ref symbol_table = self.symbol_table_handle.borrow();
+    self.global_env.populate_from_symbols(symbol_table);
+    let output = self.global_env.infer_block(&input.0)?;
+    Ok(format!("{:?}", output))
+  }
+}
+
+impl TypeEnv {
+  fn instantiate(&mut self, sigma: Scheme) -> Type {
+    match sigma {
+      Scheme { ty, .. } => ty,
+    }
+  }
+  fn generate(&mut self, ty: Type) -> Scheme {
+    Scheme {
+      names: vec![], //TODO incomplete
+      ty
+    }
+  }
+  fn infer_block(&mut self, block: &Vec<ast::Statement>) -> TypeResult<Type> {
+    let mut output = Type::Const(TConst::Unit);
+    for statement in block {
+      output = self.infer_statement(statement)?;
+    }
+    Ok(output)
+  }
+  fn infer_statement(&mut self, statement: &ast::Statement) -> TypeResult<Type> {
+    match statement {
+      ast::Statement::ExpressionStatement(expr) => self.infer_expr(expr),
+      ast::Statement::Declaration(decl) => self.infer_decl(decl)
+    }
+  }
+  fn infer_decl(&mut self, decl: &ast::Declaration) -> TypeResult<Type> {
+    use ast::Declaration::*;
+    match decl {
+      Binding { name, expr, .. } => {
+        let ty = self.infer_expr(expr)?;
+        let sigma = self.generate(ty);
+        self.0.insert(name.clone(), sigma);
+      },
+      _ => (),
+    }
+    Ok(Type::Const(TConst::Unit))
+  }
+  fn infer_expr(&mut self, expr: &ast::Expression) -> TypeResult<Type> {
+    match expr {
+      ast::Expression(expr, Some(anno)) => {
+        self.infer_exprtype(expr)
+      },
+      ast::Expression(expr, None) => {
+        self.infer_exprtype(expr)
+      }
+    }
+  }
+
+  fn infer_exprtype(&mut self, expr: &ast::ExpressionType) -> TypeResult<Type> {
+    use self::TConst::*;
+    use ast::ExpressionType::*;
+    Ok(match expr {
+      NatLiteral(_) => Type::Const(Nat),
+      StringLiteral(_) => Type::Const(StringT),
+      BinExp(op, lhs, rhs) => {
+
+        return Err(format!("NOTDONE"))
+      },
+      Call { f, arguments } =>  {
+
+        return Err(format!("NOTDONE"))
+      },
+      Value(name) => {
+        let s = match self.0.get(name) {
+          Some(sigma) => sigma.clone(),
+          None => return Err(format!("Unknown variable: {}", name))
+        };
+        self.instantiate(s)
+      },
+      _ => Type::Const(Unit)
+    })
+  }
+}
+
+
+/* GIANT TODO - use the rust im crate, unless I make this code way less haskell-ish after it's done
+  */
+
+/*
+
+
+pub type TypeResult<T> = Result<T, String>;
+*/
+
+/* TODO this should just check the name against a map, and that map should be pre-populated with
+ * types */
+/*
+impl parsing::TypeName {
+  fn to_type(&self) -> TypeResult<Type> {
+	use self::parsing::TypeSingletonName;
+	use self::parsing::TypeName::*;
+	use self::Type::*; use self::TConstOld::*;
+    Ok(match self {
+      Tuple(_) => return Err(format!("Tuples not yet implemented")),
+      Singleton(name) => match name {
+        TypeSingletonName { name, .. } => match &name[..] {
+          /*
+          "Nat" => Const(Nat),
+          "Int" => Const(Int),
+          "Float" => Const(Float),
+          "Bool" => Const(Bool),
+          "String" => Const(StringT),
+          */
+          n => Const(Custom(n.to_string()))
+        }
+      }
+    })
+  }
+}
+*/
+
+
+
+/*
+impl TypeContext {
+  pub fn type_check_ast(&mut self, ast: &parsing::AST) -> TypeResult<String> {
+    let ref block = ast.0;
+    let mut infer = Infer::default();
+    let env = TypeEnvironment::default();
+    let output = infer.infer_block(block, &env);
+    match output {
+      Ok(s) => Ok(format!("{:?}", s)),
+      Err(s) => Err(format!("Error: {:?}", s))
+    }
+  }
+}
+
+// this is the equivalent of the Haskell Infer monad
+#[derive(Debug, Default)]
+struct Infer {
+  _idents: u32,
+}
+
+#[derive(Debug)]
+enum InferError {
+  CannotUnify(MonoType, MonoType),
+  OccursCheckFailed(Rc<String>, MonoType),
+  UnknownIdentifier(Rc<String>),
+  Custom(String),
+}
+
+type InferResult<T> = Result<T, InferError>;
+
+
+impl Infer {
+  fn fresh(&mut self) -> MonoType {
+    let i = self._idents;
+    self._idents += 1;
+    let name = Rc::new(format!("{}", ('a' as u8 + 1) as char));
+    MonoType::Var(name)
+  }
+
+  fn unify(&mut self, a: MonoType, b: MonoType) -> InferResult<Substitution> {
+    use self::InferError::*; use self::MonoType::*;
+    Ok(match (a, b) {
+      (Const(ref a), Const(ref b)) if a == b => Substitution::new(),
+      (Var(ref name), ref var) => Substitution::bind_variable(name, var),
+      (ref var, Var(ref name)) => Substitution::bind_variable(name, var),
+      (Function(box a1, box b1), Function(box a2, box b2)) => {
+        let s1 = self.unify(a1, a2)?;
+        let s2 = self.unify(b1.apply_substitution(&s1), b2.apply_substitution(&s1))?;
+        s1.merge(s2)
+      },
+      (a, b) => return Err(CannotUnify(a, b))
+    })
+  }
+
+  fn infer_block(&mut self, block: &Vec<parsing::Statement>, env: &TypeEnvironment) -> InferResult<MonoType> {
+    use self::parsing::Statement;
+    let mut ret = MonoType::Const(TypeConst::Unit);
+    for statement in block.iter() {
+      ret = match statement {
+        Statement::ExpressionStatement(expr) => {
+          let (sub, ty) = self.infer_expr(expr, env)?;
+          //TODO handle substitution monadically
+
+          ty
+        }
+        Statement::Declaration(decl) => MonoType::Const(TypeConst::Unit),
+      }
+    }
+    Ok(ret)
+  }
+
+  fn infer_expr(&mut self, expr: &parsing::Expression, env: &TypeEnvironment) -> InferResult<(Substitution, MonoType)> {
+    use self::parsing::Expression;
+    match expr {
+      Expression(e, Some(anno)) => self.infer_annotated_expr(e, anno, env),
+      /*
+        let anno_ty = anno.to_type()?;
+        let ty = self.infer_exprtype(&e)?;
+        self.unify(ty, anno_ty)
+      },
+      */
+      Expression(e, None) => self.infer_exprtype(e, env)
+    }
+  }
+
+  fn infer_annotated_expr(&mut self, expr: &parsing::ExpressionType, anno: &parsing::TypeName, env: &TypeEnvironment) -> InferResult<(Substitution, MonoType)> {
+    Err(InferError::Custom(format!("exprtype not done: {:?}", expr)))
+  }
+  fn infer_exprtype(&mut self, expr: &parsing::ExpressionType, env: &TypeEnvironment) -> InferResult<(Substitution, MonoType)> {
+    use self::parsing::ExpressionType::*;
+    use self::TypeConst::*;
+    Ok(match expr {
+      NatLiteral(_) => (Substitution::new(), MonoType::Const(Nat)),
+      FloatLiteral(_) => (Substitution::new(), MonoType::Const(Float)),
+      StringLiteral(_) => (Substitution::new(), MonoType::Const(StringT)),
+      BoolLiteral(_) => (Substitution::new(), MonoType::Const(Bool)),
+      Value(name) => match env.lookup(name) {
+        Some(sigma) => {
+          let tau = self.instantiate(&sigma);
+          (Substitution::new(), tau)
+        },
+        None => return Err(InferError::UnknownIdentifier(name.clone())),
+      },
+      e => return Err(InferError::Custom(format!("Type inference for {:?} not done", e)))
+    })
+  }
+  fn instantiate(&mut self, sigma: &PolyType) -> MonoType {
+    let ref ty: MonoType = sigma.1;
+    let mut subst = Substitution::new();
+
+    for name in sigma.0.iter() {
+      let fresh_mvar = self.fresh();
+      let new = Substitution::bind_variable(name, &fresh_mvar);
+      subst = subst.merge(new);
+    }
+    ty.apply_substitution(&subst)
+  }
+}
+*/
+
+
+
+
+
+
+
+
+
+
+
+
+/* OLD STUFF DOWN HERE */
+
+
+
+/*
+impl TypeContext {
+  fn infer_block(&mut self, statements: &Vec<parsing::Statement>) -> TypeResult<Type> {
+    let mut ret_type = Type::Const(TConst::Unit);
+    for statement in statements {
+      ret_type = self.infer_statement(statement)?;
+    }
+    Ok(ret_type)
+  }
+
+  fn infer_statement(&mut self, statement: &parsing::Statement) -> TypeResult<Type> {
+    use self::parsing::Statement::*;
+    match statement {
+      ExpressionStatement(expr) => self.infer(expr),
+      Declaration(decl) => self.add_declaration(decl),
+    }
+  }
+  fn add_declaration(&mut self, decl: &parsing::Declaration) -> TypeResult<Type> {
+    use self::parsing::Declaration::*;
+    use self::Type::*;
+    match decl {
+      Binding { name, expr, .. } => {
+        let ty = self.infer(expr)?;
+        self.bindings.insert(name.clone(), ty);
+      },
+      _ => return Err(format!("other formats not done"))
+    }
+    Ok(Void)
+  }
+  fn infer(&mut self, expr: &parsing::Expression) -> TypeResult<Type> {
+    use self::parsing::Expression;
+    match expr {
+      Expression(e, Some(anno)) => {
+        let anno_ty = anno.to_type()?;
+        let ty = self.infer_exprtype(&e)?;
+        self.unify(ty, anno_ty)
+      },
+      Expression(e, None) => self.infer_exprtype(e)
+    }
+  }
+  fn infer_exprtype(&mut self, expr: &parsing::ExpressionType) -> TypeResult<Type> {
+    use self::parsing::ExpressionType::*;
+    use self::Type::*; use self::TConst::*;
+    match expr {
+      NatLiteral(_) => Ok(Const(Nat)),
+      FloatLiteral(_) => Ok(Const(Float)),
+      StringLiteral(_) => Ok(Const(StringT)),
+      BoolLiteral(_) => Ok(Const(Bool)),
+      BinExp(op, lhs, rhs) => { /* remember there are both the haskell convention talk and the write you a haskell ways to do this! */
+        match op.get_type()? {
+          Func(box t1, box Func(box t2, box t3)) => {
+            let lhs_ty = self.infer(lhs)?;
+            let rhs_ty = self.infer(rhs)?;
+            self.unify(t1, lhs_ty)?;
+            self.unify(t2, rhs_ty)?;
+            Ok(t3)
+          },
+          other => Err(format!("{:?} is not a binary function type", other))
+        }
+      },
+      PrefixExp(op, expr) => match op.get_type()? {
+        Func(box t1, box t2) => {
+          let expr_ty = self.infer(expr)?;
+          self.unify(t1, expr_ty)?;
+          Ok(t2)
+        },
+        other => Err(format!("{:?} is not a prefix op function type", other))
+      },
+      Value(name) => {
+        match self.bindings.get(name) {
+          Some(ty) => Ok(ty.clone()),
+          None => Err(format!("No binding found for variable: {}", name)),
+        }
+      },
+      Call { f, arguments } => {
+        let mut tf = self.infer(f)?;
+        for arg in arguments.iter() {
+          match tf {
+            Func(box t, box rest) => {
+              let t_arg = self.infer(arg)?;
+              self.unify(t, t_arg)?;
+              tf = rest;
+            },
+            other => return Err(format!("Function call failed to unify; last type: {:?}", other)),
+          }
+        }
+        Ok(tf)
+      },
+      TupleLiteral(expressions) => {
+        let mut types = vec![];
+        for expr in expressions {
+          types.push(self.infer(expr)?);
+        }
+        Ok(Sum(types))
+      },
+      _ => Err(format!("Type not yet implemented"))
+    }
+  }
+  fn unify(&mut self, t1: Type, t2: Type) -> TypeResult<Type> {
+    use self::Type::*;// use self::TConst::*;
+    match (t1, t2) {
+      (Const(ref a), Const(ref b)) if a == b => Ok(Const(a.clone())),
+      (a, b) => Err(format!("Types {:?} and {:?} don't unify", a, b))
+    }
+  }
+}
+*/
+
+
+#[cfg(test)]
+mod tests {
+  /*
+  use super::{Type, TConst, TypeContext};
+  use super::Type::*;
+  use super::TConst::*;
+  use std::rc::Rc;
+  use std::cell::RefCell;
+
+  macro_rules! type_test {
+    ($input:expr, $correct:expr) => {
+      {
+      let symbol_table = Rc::new(RefCell::new(SymbolTable::new()));
+      let mut tc = TypeContext::new(symbol_table);
+      let ast = ::ast::parse(::tokenizing::tokenize($input)).0.unwrap() ;
+      //tc.add_symbols(&ast);
+      assert_eq!($correct, tc.infer_block(&ast.0).unwrap())
+      }
+    }
+  }
+
+  #[test]
+  fn basic_inference() {
+    type_test!("30", Const(Nat));
+    //type_test!("fn x(a: Int): Bool {}; x(1)", TConst(Boolean));
+  }
+  */
+}

schala-lang/src/util.rs

@@ -27,7 +27,7 @@ impl<'a, T, V> ScopeStack<'a, T, V> where T: Hash + Eq {
       (Some(value), _) => Some(value),
     }
   }
-
+  //TODO rename new_scope
   pub fn new_scope(&'a self, name: Option<String>) -> ScopeStack<'a, T, V> where T: Hash + Eq {
     ScopeStack {
       parent: Some(self),
@@ -35,21 +35,8 @@ impl<'a, T, V> ScopeStack<'a, T, V> where T: Hash + Eq {
       scope_name: name,
     }
   }
-  #[allow(dead_code)]
   pub fn get_name(&self) -> Option<&String> {
     self.scope_name.as_ref()
   }
 }
 
-/// this is intended for use in tests, and does no error-handling whatsoever
-#[allow(dead_code)]
-pub fn quick_ast(input: &str) -> crate::ast::AST {
-  let tokens = crate::tokenizing::tokenize(input);
-  let mut parser = crate::parsing::Parser::new(tokens);
-  parser.parse().unwrap()
-}
-
-#[allow(unused_macros)]
-macro_rules! rc {
-  ($string:tt) => { Rc::new(stringify!($string).to_string()) }
-}

schala-repl/Cargo.toml

@@ -2,22 +2,24 @@
 name = "schala-repl"
 version = "0.1.0"
 authors = ["greg <greg.shuflin@protonmail.com>"]
-edition = "2018"
 
 [dependencies]
-llvm-sys = "70.0.2"
-take_mut = "0.2.2"
+llvm-sys = "*"
+take_mut = "0.1.3"
 itertools = "0.5.8"
-getopts = "0.2.18"
+getopts = "*"
 lazy_static = "0.2.8"
 maplit = "*"
-colored = "1.8"
-serde = "1.0.91"
-serde_derive = "1.0.91"
-serde_json = "1.0.15"
+colored = "1.5"
+serde = "1.0.15"
+serde_derive = "1.0.15"
+serde_json = "1.0.3"
+rocket = "0.3.13"
+rocket_codegen = "0.3.13"
+rocket_contrib = "0.3.13"
 phf = "0.7.12"
 includedir = "0.2.0"
-linefeed = "0.6.0"
+linefeed = "0.5.0"
 regex = "0.2"
 
 [build-dependencies]

schala-repl/src/language.rs

@@ -1,80 +1,215 @@
+use std::collections::HashMap;
+use colored::*;
+use std::fmt::Write;
 use std::time;
-use std::collections::HashSet;
+
+pub struct LLVMCodeString(pub String);
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct EvalOptions {
+  pub execution_method: ExecutionMethod,
+  pub debug_passes: HashMap<String, PassDebugOptionsDescriptor>,
+}
+
+#[derive(Debug, Hash, PartialEq)]
+pub struct PassDescriptor {
+  pub name: String,
+  pub debug_options: Vec<String>
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct PassDebugOptionsDescriptor {
+  pub opts: Vec<String>,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub enum ExecutionMethod {
+  Compile,
+  Interpret,
+}
+impl Default for ExecutionMethod {
+  fn default() -> ExecutionMethod {
+    ExecutionMethod::Interpret
+  }
+}
+
+#[derive(Debug, Default)]
+pub struct UnfinishedComputation {
+  artifacts: Vec<(String, TraceArtifact)>,
+  pub durations: Vec<time::Duration>,
+  pub cur_debug_options: Vec<String>,
+}
+
+#[derive(Debug)]
+pub struct FinishedComputation {
+  artifacts: Vec<(String, TraceArtifact)>,
+  durations: Vec<time::Duration>,
+  text_output: Result<String, String>,
+}
+
+impl UnfinishedComputation {
+  pub fn add_artifact(&mut self, artifact: TraceArtifact) {
+    self.artifacts.push((artifact.stage_name.clone(), artifact));
+  }
+  pub fn finish(self, text_output: Result<String, String>) -> FinishedComputation {
+    FinishedComputation {
+      artifacts: self.artifacts,
+      text_output,
+      durations: self.durations
+    }
+  }
+  pub fn output(self, output: Result<String, String>) -> FinishedComputation {
+    FinishedComputation {
+      artifacts: self.artifacts,
+      text_output: output,
+      durations: self.durations,
+    }
+  }
+}
+
+impl FinishedComputation {
+  pub fn to_repl(&self) -> String {
+    let mut buf = String::new();
+    for (stage, artifact) in self.artifacts.iter() {
+      let color = artifact.text_color;
+      let stage = stage.color(color).bold();
+      let output = artifact.debug_output.color(color);
+      write!(&mut buf, "{}: {}\n", stage, output).unwrap();
+    }
+
+    let debug_timing = true;
+    if debug_timing {
+      write!(&mut buf, "Timing: ").unwrap();
+      for duration in self.durations.iter() {
+        let timing = (duration.as_secs() as f64) + (duration.subsec_nanos() as f64 * 1e-9);
+        write!(&mut buf, "{}s, ", timing).unwrap()
+      }
+      write!(&mut buf, "\n").unwrap();
+    }
+    match self.text_output {
+      Ok(ref output) => write!(&mut buf, "{}", output).unwrap(),
+      Err(ref err) => write!(&mut buf, "{} {}", "Error: ".red().bold(), err).unwrap(),
+    }
+    buf
+  }
+  pub fn to_noninteractive(&self) -> Option<String> {
+    match self.text_output {
+      Ok(_) => {
+        let mut buf = String::new();
+        for (stage, artifact) in self.artifacts.iter() {
+          let color = artifact.text_color;
+          let stage = stage.color(color).bold();
+          let output = artifact.debug_output.color(color);
+          write!(&mut buf, "{}: {}\n", stage, output).unwrap();
+        }
+        if buf == "" { None } else { Some(buf) }
+      },
+      Err(ref s) => Some(format!("{} {}", "Error: ".red().bold(), s))
+    }
+  }
+}
+
+#[derive(Debug)]
+pub struct TraceArtifact {
+  stage_name: String,
+  debug_output: String,
+  text_color: &'static str,
+}
+
+impl TraceArtifact {
+  pub fn new(stage: &str, debug: String) -> TraceArtifact {
+    let color = match stage {
+      "parse_trace"  | "ast" => "red",
+      "ast_reducing" => "red",
+      "tokens" => "green",
+      "type_check" => "magenta",
+      _ => "blue",
+    };
+    TraceArtifact { stage_name: stage.to_string(), debug_output: debug, text_color: color}
+  }
+
+  pub fn new_parse_trace(trace: Vec<String>) -> TraceArtifact {
+    let mut output = String::new();
+
+    for t in trace {
+      output.push_str(&t);
+      output.push_str("\n");
+    }
+
+    TraceArtifact { stage_name: "parse_trace".to_string(), debug_output: output, text_color: "red"}
+  }
+}
 
 pub trait ProgrammingLanguageInterface {
+  fn execute_pipeline(&mut self, _input: &str, _eval_options: &EvalOptions) -> FinishedComputation {
+    FinishedComputation { artifacts: vec![], text_output: Err(format!("Execution pipeline not done")), durations: vec![] }
+  }
+
   fn get_language_name(&self) -> String;
   fn get_source_file_suffix(&self) -> String;
+  fn get_passes(&self) -> Vec<PassDescriptor> {
+    vec![]
+  }
+  fn handle_custom_interpreter_directives(&mut self, _commands: &Vec<&str>) -> Option<String> {
+    None
+  }
+  fn custom_interpreter_directives_help(&self) -> String {
+    format!(">> No custom interpreter directives specified <<")
+  }
+}
 
-  fn run_computation(&mut self, _request: ComputationRequest) -> ComputationResponse {
-    ComputationResponse {
-      main_output: Err(format!("Computation pipeline not implemented")),
-      global_output_stats: GlobalOutputStats::default(),
-      debug_responses: vec![],
+/* a pass_chain function signature looks like: 
+ * fn(&mut ProgrammingLanguageInterface, A, Option<&mut DebugHandler>) -> Result<B, String>
+ *
+ * TODO use some kind of failure-handling library to make this better
+ */
+
+#[macro_export]
+macro_rules! pass_chain {
+  ($state:expr, $options:expr; $($pass:path), *) => {
+    |text_input| {
+      let mut comp = UnfinishedComputation::default();
+      pass_chain_helper! { ($state, comp, $options); text_input $(, $pass)* }
     }
-  }
-
-  fn request_meta(&mut self, _request: LangMetaRequest) -> LangMetaResponse {
-    LangMetaResponse::Custom { kind: format!("not-implemented"), value: format!("") }
-  }
+  };
 }
 
-pub struct ComputationRequest<'a> {
-  pub source: &'a str,
-  pub debug_requests: HashSet<DebugAsk>,
-}
-
-pub struct ComputationResponse {
-  pub main_output: Result<String, String>,
-  pub global_output_stats: GlobalOutputStats,
-  pub debug_responses: Vec<DebugResponse>,
-}
-
-#[derive(Default, Debug)]
-pub struct GlobalOutputStats {
-  pub total_duration: time::Duration,
-  pub stage_durations: Vec<(String, time::Duration)>
-}
-
-#[derive(Debug, Clone, Hash, Eq, PartialEq, Deserialize, Serialize)]
-pub enum DebugAsk {
-  Timing,
-  ByStage { stage_name: String, token: Option<String> },
-}
-
-impl DebugAsk {
-  pub fn is_for_stage(&self, name: &str) -> bool {
-    match self {
-      DebugAsk::ByStage { stage_name, .. } if stage_name == name => true,
-      _ => false
+#[macro_export]
+macro_rules! pass_chain_helper {
+  (($state:expr, $comp:expr, $options:expr); $input:expr, $pass:path $(, $rest:path)*) => {
+    {
+      use std::time;
+      use schala_repl::PassDebugOptionsDescriptor;
+      let pass_name = stringify!($pass);
+      let (output, duration) = {
+        let ref debug_map = $options.debug_passes;
+        let debug_handle = match debug_map.get(pass_name) {
+          Some(PassDebugOptionsDescriptor { opts }) => {
+            let ptr = &mut $comp;
+            ptr.cur_debug_options = opts.clone();
+            Some(ptr)
+          }
+          _ => None
+        };
+        let start = time::Instant::now();
+        let pass_output = $pass($state, $input, debug_handle);
+        let elapsed = start.elapsed();
+        (pass_output, elapsed)
+      };
+      $comp.durations.push(duration);
+      match output {
+        Ok(result) => pass_chain_helper! { ($state, $comp, $options); result $(, $rest)* },
+        Err(err) => {
+          $comp.output(Err(format!("Pass {} failed with {:?}", pass_name, err)))
+        }
+      }
     }
-  }
-}
-
-pub struct DebugResponse {
-  pub ask: DebugAsk,
-  pub value: String
-}
-
-pub enum LangMetaRequest {
-  StageNames,
-  Docs {
-    source: String,
-  },
-  Custom {
-    kind: String,
-    value: String
-  },
-  ImmediateDebug(DebugAsk),
-}
-
-pub enum LangMetaResponse {
-  StageNames(Vec<String>),
-  Docs {
-    doc_string: String,
-  },
-  Custom {
-    kind: String,
-    value: String
-  },
-  ImmediateDebug(DebugResponse),
+  };
+  // Done
+  (($state:expr, $comp:expr, $options:expr); $final_output:expr) => {
+    {
+      let final_output: FinishedComputation = $comp.finish(Ok($final_output));
+      final_output
+    }
+  };
 }

schala-repl/src/lib.rs

@@ -1,6 +1,7 @@
 #![feature(link_args)]
-#![feature(slice_patterns, box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
+#![feature(slice_patterns, box_patterns, box_syntax)]
 #![feature(plugin)]
+#![plugin(rocket_codegen)]
 extern crate getopts;
 extern crate linefeed;
 extern crate itertools;
@@ -9,49 +10,91 @@ extern crate colored;
 #[macro_use]
 extern crate serde_derive;
 extern crate serde_json;
+extern crate rocket;
+extern crate rocket_contrib;
 extern crate includedir;
 extern crate phf;
 
-use std::collections::HashSet;
 use std::path::Path;
 use std::fs::File;
-use std::io::Read;
+use std::io::{Read, Write};
 use std::process::exit;
+use std::default::Default;
+use std::fmt::Write as FmtWrite;
+
+use colored::*;
+use itertools::Itertools;
 
-mod repl;
 mod language;
+mod webapp;
+pub mod llvm_wrap;
 
-pub use language::{ProgrammingLanguageInterface,
-ComputationRequest, ComputationResponse,
-LangMetaRequest, LangMetaResponse,
-DebugResponse, DebugAsk, GlobalOutputStats};
-
-include!(concat!(env!("OUT_DIR"), "/static.rs"));
 const VERSION_STRING: &'static str = "0.1.0";
 
-pub fn start_repl(langs: Vec<Box<dyn ProgrammingLanguageInterface>>) {
-  let options = command_line_options().parse(std::env::args()).unwrap_or_else(|e| {
+include!(concat!(env!("OUT_DIR"), "/static.rs"));
+
+pub use language::{LLVMCodeString, ProgrammingLanguageInterface, EvalOptions,
+  ExecutionMethod, TraceArtifact, FinishedComputation, UnfinishedComputation, PassDebugOptionsDescriptor, PassDescriptor};
+
+pub type PLIGenerator = Box<Fn() -> Box<ProgrammingLanguageInterface> + Send + Sync>;
+
+pub fn repl_main(generators: Vec<PLIGenerator>) {
+  let languages: Vec<Box<ProgrammingLanguageInterface>> = generators.iter().map(|x| x()).collect();
+
+  let option_matches = program_options().parse(std::env::args()).unwrap_or_else(|e| {
     println!("{:?}", e);
     exit(1);
   });
 
-  if options.opt_present("help") {
-    println!("{}", command_line_options().usage("Schala metainterpreter"));
+  if option_matches.opt_present("list-languages") {
+    for lang in languages {
+      println!("{}", lang.get_language_name());
+    }
+    exit(1);
+  }
+
+  if option_matches.opt_present("help") {
+    println!("{}", program_options().usage("Schala metainterpreter"));
     exit(0);
   }
 
-  match options.free[..] {
+  if option_matches.opt_present("webapp") {
+    webapp::web_main(generators);
+    exit(0);
+  }
+
+  let mut options = EvalOptions::default();
+  let debug_passes = if let Some(opts) = option_matches.opt_str("debug") {
+    let output: Vec<String> = opts.split_terminator(",").map(|s| s.to_string()).collect();
+    output
+  } else {
+    vec![]
+  };
+
+  let language_names: Vec<String> = languages.iter().map(|lang| {lang.get_language_name()}).collect();
+  let initial_index: usize =
+    option_matches.opt_str("lang")
+    .and_then(|lang| { language_names.iter().position(|x| { x.to_lowercase() == lang.to_lowercase() }) })
+    .unwrap_or(0);
+
+  options.execution_method = match option_matches.opt_str("eval-style") {
+    Some(ref s) if s == "compile" => ExecutionMethod::Compile,
+    _ => ExecutionMethod::Interpret,
+  };
+
+  match option_matches.free[..] {
     [] | [_] => {
-      let mut repl = repl::Repl::new(langs);
-      repl.run_repl();
+      let mut repl = Repl::new(languages, initial_index);
+      repl.run();
     }
-    [_, ref filename, ..] => {
-      run_noninteractive(filename, langs);
+    [_, ref filename, _..] => {
+
+      run_noninteractive(filename, languages, options, debug_passes);
     }
   };
 }
 
-fn run_noninteractive(filename: &str, languages: Vec<Box<dyn ProgrammingLanguageInterface>>) {
+fn run_noninteractive(filename: &str, languages: Vec<Box<ProgrammingLanguageInterface>>, mut options: EvalOptions, debug_passes: Vec<String>) {
   let path = Path::new(filename);
   let ext = path.extension().and_then(|e| e.to_str()).unwrap_or_else(|| {
     println!("Source file lacks extension");
@@ -65,28 +108,454 @@ fn run_noninteractive(filename: &str, languages: Vec<Box<dyn ProgrammingLanguage
 
   let mut source_file = File::open(path).unwrap();
   let mut buffer = String::new();
+
   source_file.read_to_string(&mut buffer).unwrap();
 
-  let request = ComputationRequest {
-    source: &buffer,
-    debug_requests: HashSet::new(),
-  };
+  for pass in debug_passes.into_iter() {
+    if let Some(_) = language.get_passes().iter().find(|desc| desc.name == pass) {
+      options.debug_passes.insert(pass, PassDebugOptionsDescriptor { opts: vec![] });
+    }
+  }
 
-  let response = language.run_computation(request);
-  match response.main_output {
-    Ok(s) => println!("{}", s),
-    Err(s) => println!("{}", s)
-  };
+  match options.execution_method {
+    ExecutionMethod::Compile => {
+      /*
+      let llvm_bytecode = language.compile(&buffer);
+      compilation_sequence(llvm_bytecode, filename);
+      */
+      panic!("Not ready to go yet");
+    },
+    ExecutionMethod::Interpret => {
+      let output = language.execute_pipeline(&buffer, &options);
+      output.to_noninteractive().map(|text| println!("{}", text));
+    }
+  }
 }
 
+#[derive(Clone)]
+enum CommandTree {
+  Terminal(String, Option<String>),
+  NonTerminal(String, Vec<CommandTree>, Option<String>),
+  Top(Vec<CommandTree>),
+}
 
-fn command_line_options() -> getopts::Options {
+impl CommandTree {
+  fn term(s: &str, help: Option<&str>) -> CommandTree {
+    CommandTree::Terminal(s.to_string(), help.map(|x| x.to_string()))
+  }
+  fn get_cmd(&self) -> String {
+    match self {
+      CommandTree::Terminal(s, _) => s.to_string(),
+      CommandTree::NonTerminal(s, _, _) => s.to_string(),
+      CommandTree::Top(_) => "".to_string(),
+    }
+  }
+  fn get_help(&self) -> String {
+    match self {
+      CommandTree::Terminal(_, h) => h.as_ref().map(|h| h.clone()).unwrap_or(format!("")),
+      CommandTree::NonTerminal(_, _, h) => h.as_ref().map(|h| h.clone()).unwrap_or(format!("")),
+      CommandTree::Top(_) => "".to_string(),
+    }
+  }
+  fn get_children(&self) -> Vec<String> {
+    match self {
+      CommandTree::Terminal(_, _) => vec![],
+      CommandTree::NonTerminal(_, children, _) => children.iter().map(|x| x.get_cmd()).collect(),
+      CommandTree::Top(children) => children.iter().map(|x| x.get_cmd()).collect(),
+    }
+  }
+}
+
+struct TabCompleteHandler {
+  sigil: char,
+  top_level_commands: CommandTree,
+}
+
+use linefeed::complete::{Completion, Completer};
+use linefeed::terminal::Terminal;
+
+impl TabCompleteHandler {
+  fn new(sigil: char, top_level_commands: CommandTree) -> TabCompleteHandler {
+    TabCompleteHandler {
+      top_level_commands,
+      sigil,
+    }
+  }
+}
+
+impl<T: Terminal> Completer<T> for TabCompleteHandler {
+  fn complete(&self, word: &str, prompter: &linefeed::prompter::Prompter<T>, start: usize, _end: usize) -> Option<Vec<Completion>> {
+    let line = prompter.buffer();
+
+    if line.starts_with(&format!("{}", self.sigil)) {
+      let mut words = line[1..(if start == 0 { 1 } else { start })].split_whitespace();
+      let mut completions = Vec::new();
+      let mut command_tree: Option<&CommandTree> = Some(&self.top_level_commands);
+
+      loop {
+        match words.next() {
+          None => {
+            let top = match command_tree {
+              Some(CommandTree::Top(_)) => true,
+              _ => false
+            };
+            let word = if top { word.get(1..).unwrap() } else { word };
+            for cmd in command_tree.map(|x| x.get_children()).unwrap_or(vec![]).into_iter() {
+              if cmd.starts_with(word) {
+                completions.push(Completion {
+                    completion: format!("{}{}", if top { ":" } else { "" }, cmd),
+                    display: Some(cmd.clone()),
+                    suffix: linefeed::complete::Suffix::Some(' ')
+                })
+              }
+            }
+            break;
+          },
+          Some(s) => {
+            let new_ptr: Option<&CommandTree> = command_tree.and_then(|cm| match cm {
+              CommandTree::Top(children) => children.iter().find(|c| c.get_cmd() == s),
+              CommandTree::NonTerminal(_, children, _) => children.iter().find(|c| c.get_cmd() == s),
+              CommandTree::Terminal(_, _) => None,
+            });
+            command_tree = new_ptr;
+          }
+        }
+      }
+      Some(completions)
+    } else {
+      None
+    }
+  }
+}
+
+struct Repl {
+  options: EvalOptions,
+  languages: Vec<Box<ProgrammingLanguageInterface>>,
+  current_language_index: usize,
+  interpreter_directive_sigil: char,
+  line_reader: linefeed::interface::Interface<linefeed::terminal::DefaultTerminal>,
+}
+
+impl Repl {
+  fn new(languages: Vec<Box<ProgrammingLanguageInterface>>, initial_index: usize) -> Repl {
+    use linefeed::Interface;
+    let i = if initial_index < languages.len() { initial_index } else { 0 };
+
+    let line_reader = Interface::new("schala-repl").unwrap();
+
+    Repl {
+      options: Repl::get_options(),
+      languages: languages,
+      current_language_index: i,
+      interpreter_directive_sigil: ':',
+      line_reader
+    }
+  }
+
+  fn get_cur_language(&self) -> &ProgrammingLanguageInterface {
+    self.languages[self.current_language_index].as_ref()
+  }
+
+  fn get_options() -> EvalOptions {
+    File::open(".schala_repl")
+      .and_then(|mut file| {
+        let mut contents = String::new();
+        file.read_to_string(&mut contents)?;
+        Ok(contents)
+      })
+      .and_then(|contents| {
+        let options: EvalOptions = serde_json::from_str(&contents)?;
+        Ok(options)
+      }).unwrap_or(EvalOptions::default())
+  }
+
+  fn save_options(&self) {
+    let ref options = self.options;
+    let read = File::create(".schala_repl")
+      .and_then(|mut file| {
+        let buf = serde_json::to_string(options).unwrap();
+        file.write_all(buf.as_bytes())
+      });
+
+    if let Err(err) = read {
+      println!("Error saving .schala_repl file {}", err);
+    }
+  }
+
+  fn run(&mut self) {
+    use linefeed::ReadResult;
+
+    println!("Schala MetaInterpreter version {}", VERSION_STRING);
+    println!("Type {}help for help with the REPL", self.interpreter_directive_sigil);
+
+    self.line_reader.load_history(".schala_history").unwrap_or(());
+
+    loop {
+      let language_name = self.languages[self.current_language_index].get_language_name();
+      let directives = self.get_directives();
+      let tab_complete_handler = TabCompleteHandler::new(self.interpreter_directive_sigil, directives);
+      self.line_reader.set_completer(std::sync::Arc::new(tab_complete_handler));
+
+      let prompt_str = format!("{} >> ", language_name);
+      self.line_reader.set_prompt(&prompt_str);
+
+      match self.line_reader.read_line() {
+        Err(e) => {
+          println!("Terminal read error: {}", e);
+        },
+        Ok(ReadResult::Eof) => break,
+        Ok(ReadResult::Signal(_)) => break,
+        Ok(ReadResult::Input(ref input)) => {
+          self.line_reader.add_history_unique(input.to_string());
+          let output = match input.chars().nth(0) {
+            Some(ch) if ch == self.interpreter_directive_sigil => self.handle_interpreter_directive(input),
+            _ => Some(self.input_handler(input)),
+          };
+          if let Some(o) = output {
+            println!("=> {}", o);
+          }
+        }
+      }
+    }
+    self.line_reader.save_history(".schala_history").unwrap_or(());
+    self.save_options();
+    println!("Exiting...");
+  }
+
+  fn input_handler(&mut self, input: &str) -> String {
+    let ref mut language = self.languages[self.current_language_index];
+    let interpreter_output = language.execute_pipeline(input, &self.options);
+    interpreter_output.to_repl()
+  }
+
+  fn get_directives(&self) -> CommandTree {
+    let ref passes = self.get_cur_language().get_passes();
+
+    let passes_directives: Vec<CommandTree> = passes.iter()
+      .map(|pass_descriptor| {
+        let name = &pass_descriptor.name;
+        if pass_descriptor.debug_options.len() == 0 {
+          CommandTree::term(name, None)
+        } else {
+          let sub_opts: Vec<CommandTree> = pass_descriptor.debug_options.iter()
+            .map(|o| CommandTree::term(o, None)).collect();
+          CommandTree::NonTerminal(
+            name.clone(),
+            sub_opts,
+            None
+          )
+        }
+      }).collect();
+
+    CommandTree::Top(vec![
+      CommandTree::term("exit", Some("exit the REPL")),
+      CommandTree::term("quit", Some("exit the REPL")),
+      CommandTree::term("help", Some("Print this help message")),
+      CommandTree::NonTerminal(format!("debug"), vec![
+        CommandTree::term("passes", None),
+        CommandTree::NonTerminal(format!("show"), passes_directives.clone(), None),
+        CommandTree::NonTerminal(format!("hide"), passes_directives.clone(), None),
+      ], Some(format!("show or hide pass info for a given pass, or display the names of all passes"))),
+      CommandTree::NonTerminal(format!("lang"), vec![
+        CommandTree::term("next", None),
+        CommandTree::term("prev", None),
+        CommandTree::NonTerminal(format!("go"), vec![], None)//TODO
+      ], Some(format!("switch between languages, or go directly to a langauge by name"))),
+    ])
+  }
+
+  fn handle_interpreter_directive(&mut self, input: &str) -> Option<String> {
+    let mut iter = input.chars();
+    iter.next();
+    let commands: Vec<&str> = iter
+      .as_str()
+      .split_whitespace()
+      .collect();
+
+    let cmd: &str = match commands.get(0).clone() {
+      None => return None,
+      Some(s) => s
+    };
+
+    match cmd {
+      "exit" | "quit"  => {
+        self.save_options();
+        exit(0)
+      },
+      "lang" | "language" => match commands.get(1) {
+        Some(&"show") => {
+          let mut buf = String::new();
+          for (i, lang) in self.languages.iter().enumerate() {
+            write!(buf, "{}{}\n", if i == self.current_language_index { "* "} else { "" }, lang.get_language_name()).unwrap();
+          }
+          Some(buf)
+        },
+        Some(&"go") => match commands.get(2) {
+          None => Some(format!("Must specify a language name")),
+          Some(&desired_name) => {
+            for (i, _) in self.languages.iter().enumerate() {
+              let lang_name = self.languages[i].get_language_name();
+              if lang_name.to_lowercase() == desired_name.to_lowercase() {
+                self.current_language_index = i;
+                return Some(format!("Switching to {}", self.languages[self.current_language_index].get_language_name()));
+              }
+            }
+            Some(format!("Language {} not found", desired_name))
+          }
+        },
+        Some(&"next") | Some(&"n") => {
+          self.current_language_index = (self.current_language_index + 1) % self.languages.len();
+          Some(format!("Switching to {}", self.languages[self.current_language_index].get_language_name()))
+        },
+        Some(&"previous") | Some(&"p") | Some(&"prev") => { 
+          self.current_language_index = if self.current_language_index == 0 { self.languages.len() - 1 } else { self.current_language_index - 1 };
+          Some(format!("Switching to {}", self.languages[self.current_language_index].get_language_name()))
+        },
+        Some(e) => Some(format!("Bad `lang(uage)` argument: {}", e)),
+        None => Some(format!("Valid arguments for `lang(uage)` are `show`, `next`|`n`, `previous`|`prev`|`n`"))
+      },
+      "help" =>  {
+        let mut buf = String::new();
+        let ref lang = self.languages[self.current_language_index];
+        let directives = match self.get_directives() {
+            CommandTree::Top(children) => children,
+            _ => panic!("Top-level CommandTree not Top")
+        };
+
+        writeln!(buf, "MetaInterpreter options").unwrap();
+        writeln!(buf, "-----------------------").unwrap();
+
+        for directive in directives {
+          let trailer = " ";
+          writeln!(buf, "{}{}- {}", directive.get_cmd(), trailer, directive.get_help()).unwrap();
+        }
+
+        writeln!(buf, "").unwrap();
+        writeln!(buf, "Language-specific help for {}", lang.get_language_name()).unwrap();
+        writeln!(buf, "-----------------------").unwrap();
+        writeln!(buf, "{}", lang.custom_interpreter_directives_help()).unwrap();
+        Some(buf)
+      },
+      "debug" => self.handle_debug(commands),
+      e => self.languages[self.current_language_index]
+        .handle_custom_interpreter_directives(&commands)
+        .or(Some(format!("Unknown command: {}", e)))
+    }
+  }
+  fn handle_debug(&mut self, commands: Vec<&str>) -> Option<String> {
+    let passes = self.get_cur_language().get_passes();
+    match commands.get(1) {
+      Some(&"passes") => Some(
+        passes.into_iter()
+        .map(|desc| {
+          if self.options.debug_passes.contains_key(&desc.name) {
+            let color = "green";
+            format!("*{}", desc.name.color(color))
+          } else {
+            desc.name
+          }
+        })
+        .intersperse(format!(" -> "))
+        .collect()),
+      b @ Some(&"show") | b @ Some(&"hide") => {
+        let show = b == Some(&"show");
+        let debug_pass: String = match commands.get(2) {
+          Some(s) => s.to_string(),
+          None => return Some(format!("Must specify a stage to debug")),
+        };
+        let pass_opt = commands.get(3);
+        if let Some(desc) = passes.iter().find(|desc| desc.name == debug_pass) {
+          let mut opts = vec![];
+          if let Some(opt) = pass_opt {
+            opts.push(opt.to_string());
+          }
+          let msg = format!("{} debug for pass {}", if show { "Enabling" } else { "Disabling" }, debug_pass);
+          if show {
+            self.options.debug_passes.insert(desc.name.clone(), PassDebugOptionsDescriptor { opts });
+          } else {
+            self.options.debug_passes.remove(&desc.name);
+          }
+          Some(msg)
+        } else {
+          Some(format!("Couldn't find stage: {}", debug_pass))
+        }
+      },
+      _ => Some(format!("Unknown debug command"))
+    }
+  }
+}
+
+/*
+pub fn compilation_sequence(llvm_code: LLVMCodeString, sourcefile: &str) {
+    use std::process::Command;
+
+    let ll_filename = "out.ll";
+    let obj_filename = "out.o";
+    let q: Vec<&str> = sourcefile.split('.').collect();
+    let bin_filename = match &q[..] {
+        &[name, "maaru"] => name,
+        _ => panic!("Bad filename {}", sourcefile),
+    };
+
+    let LLVMCodeString(llvm_str) = llvm_code;
+
+    println!("Compilation process finished for {}", ll_filename);
+    File::create(ll_filename)
+        .and_then(|mut f| f.write_all(llvm_str.as_bytes()))
+        .expect("Error writing file");
+
+    let llc_output = Command::new("llc")
+        .args(&["-filetype=obj", ll_filename, "-o", obj_filename])
+        .output()
+        .expect("Failed to run llc");
+
+
+    if !llc_output.status.success() {
+        println!("{}", String::from_utf8_lossy(&llc_output.stderr));
+    }
+
+    let gcc_output = Command::new("gcc")
+        .args(&["-o", bin_filename, &obj_filename])
+        .output()
+        .expect("failed to run gcc");
+
+    if !gcc_output.status.success() {
+        println!("{}", String::from_utf8_lossy(&gcc_output.stdout));
+        println!("{}", String::from_utf8_lossy(&gcc_output.stderr));
+    }
+
+    for filename in [obj_filename].iter() {
+        Command::new("rm")
+            .arg(filename)
+            .output()
+            .expect(&format!("failed to run rm {}", filename));
+    }
+}
+*/
+
+fn program_options() -> getopts::Options {
   let mut options = getopts::Options::new();
+  options.optopt("s",
+                 "eval-style",
+                 "Specify whether to compile (if supported) or interpret the language. If not specified, the default is language-specific",
+                 "[compile|interpret]"
+                 );
+  options.optflag("",
+                  "list-languages",
+                  "Show a list of all supported languages");
+  options.optopt("l",
+                 "lang",
+                 "Start up REPL in a language",
+                 "LANGUAGE");
   options.optflag("h",
                   "help",
                   "Show help text");
   options.optflag("w",
                   "webapp",
                   "Start up web interpreter");
+  options.optopt("d",
+                  "debug",
+                  "Debug a stage (l = tokenizer, a = AST, r = parse trace, s = symbol table)",
+                  "[l|a|r|s]");
   options
 }

schala-repl/src/llvm_wrap.rs

@@ -0,0 +1,279 @@
+#![allow(non_snake_case)]
+#![allow(dead_code)]
+extern crate llvm_sys;
+
+use self::llvm_sys::{LLVMIntPredicate, LLVMRealPredicate};
+use self::llvm_sys::prelude::*;
+use self::llvm_sys::core;
+use std::ptr;
+use std::ffi::{CString, CStr};
+use std::os::raw::c_char;
+
+pub fn create_context() -> LLVMContextRef {
+    unsafe { core::LLVMContextCreate() }
+}
+pub fn module_create_with_name(name: &str) -> LLVMModuleRef {
+    unsafe {
+        let n = name.as_ptr() as *const _;
+        core::LLVMModuleCreateWithName(n)
+    }
+}
+pub fn CreateBuilderInContext(context: LLVMContextRef) -> LLVMBuilderRef {
+    unsafe { core::LLVMCreateBuilderInContext(context) }
+}
+
+pub fn AppendBasicBlockInContext(context: LLVMContextRef,
+                                 function: LLVMValueRef,
+                                 name: &str)
+                                 -> LLVMBasicBlockRef {
+    let c_name = CString::new(name).unwrap();
+    unsafe { core::LLVMAppendBasicBlockInContext(context, function, c_name.as_ptr()) }
+}
+
+pub fn AddFunction(module: LLVMModuleRef, name: &str, function_type: LLVMTypeRef) -> LLVMValueRef {
+    let c_name = CString::new(name).unwrap();
+    unsafe { core::LLVMAddFunction(module, c_name.as_ptr(), function_type) }
+}
+
+pub fn FunctionType(return_type: LLVMTypeRef,
+                    mut param_types: Vec<LLVMTypeRef>,
+                    is_var_rag: bool)
+                    -> LLVMTypeRef {
+    let len = param_types.len();
+    unsafe {
+        let pointer = param_types.as_mut_ptr();
+        core::LLVMFunctionType(return_type,
+                               pointer,
+                               len as u32,
+                               if is_var_rag { 1 } else { 0 })
+    }
+}
+
+pub fn GetNamedFunction(module: LLVMModuleRef,
+                        name: &str) -> Option<LLVMValueRef> {
+
+    let c_name = CString::new(name).unwrap();
+    let ret = unsafe { core::LLVMGetNamedFunction(module, c_name.as_ptr()) };
+
+    if ret.is_null() {
+        None
+    } else {
+        Some(ret)
+    }
+}
+
+pub fn VoidTypeInContext(context: LLVMContextRef) -> LLVMTypeRef {
+    unsafe { core::LLVMVoidTypeInContext(context) }
+}
+
+pub fn DisposeBuilder(builder: LLVMBuilderRef) {
+    unsafe { core::LLVMDisposeBuilder(builder) }
+}
+
+pub fn DisposeModule(module: LLVMModuleRef) {
+    unsafe { core::LLVMDisposeModule(module) }
+}
+
+pub fn ContextDispose(context: LLVMContextRef) {
+    unsafe { core::LLVMContextDispose(context) }
+}
+
+pub fn PositionBuilderAtEnd(builder: LLVMBuilderRef, basic_block: LLVMBasicBlockRef) {
+    unsafe { core::LLVMPositionBuilderAtEnd(builder, basic_block) }
+}
+
+pub fn BuildRet(builder: LLVMBuilderRef, val: LLVMValueRef) -> LLVMValueRef {
+    unsafe { core::LLVMBuildRet(builder, val) }
+}
+
+pub fn BuildRetVoid(builder: LLVMBuilderRef) -> LLVMValueRef {
+    unsafe { core::LLVMBuildRetVoid(builder) }
+}
+
+pub fn DumpModule(module: LLVMModuleRef) {
+    unsafe { core::LLVMDumpModule(module) }
+}
+
+pub fn Int64TypeInContext(context: LLVMContextRef) -> LLVMTypeRef {
+    unsafe { core::LLVMInt64TypeInContext(context) }
+}
+
+pub fn ConstInt(int_type: LLVMTypeRef, n: u64, sign_extend: bool) -> LLVMValueRef {
+    unsafe { core::LLVMConstInt(int_type, n, if sign_extend { 1 } else { 0 }) }
+}
+
+pub fn BuildAdd(builder: LLVMBuilderRef,
+                lhs: LLVMValueRef,
+                rhs: LLVMValueRef,
+                reg_name: &str)
+                -> LLVMValueRef {
+    let name = CString::new(reg_name).unwrap();
+    unsafe { core::LLVMBuildAdd(builder, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildSub(builder: LLVMBuilderRef,
+                lhs: LLVMValueRef,
+                rhs: LLVMValueRef,
+                reg_name: &str)
+                -> LLVMValueRef {
+    let name = CString::new(reg_name).unwrap();
+    unsafe { core::LLVMBuildSub(builder, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildMul(builder: LLVMBuilderRef,
+                lhs: LLVMValueRef,
+                rhs: LLVMValueRef,
+                reg_name: &str)
+                -> LLVMValueRef {
+    let name = CString::new(reg_name).unwrap();
+    unsafe { core::LLVMBuildMul(builder, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildUDiv(builder: LLVMBuilderRef,
+                 lhs: LLVMValueRef,
+                 rhs: LLVMValueRef,
+                 reg_name: &str)
+                 -> LLVMValueRef {
+    let name = CString::new(reg_name).unwrap();
+    unsafe { core::LLVMBuildUDiv(builder, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildSRem(builder: LLVMBuilderRef,
+                 lhs: LLVMValueRef,
+                 rhs: LLVMValueRef,
+                 reg_name: &str)
+                 -> LLVMValueRef {
+    let name = CString::new(reg_name).unwrap();
+    unsafe { core::LLVMBuildSRem(builder, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildCondBr(builder: LLVMBuilderRef,
+                   if_expr: LLVMValueRef,
+                   then_expr: LLVMBasicBlockRef,
+                   else_expr: LLVMBasicBlockRef) -> LLVMValueRef {
+
+
+    unsafe { core::LLVMBuildCondBr(builder, if_expr, then_expr, else_expr) }
+}
+
+pub fn BuildBr(builder: LLVMBuilderRef,
+               dest: LLVMBasicBlockRef) -> LLVMValueRef {
+    unsafe { core::LLVMBuildBr(builder, dest) }
+}
+
+pub fn GetInsertBlock(builder: LLVMBuilderRef) -> LLVMBasicBlockRef {
+    unsafe { core::LLVMGetInsertBlock(builder) }
+}
+
+pub fn BuildPhi(builder: LLVMBuilderRef, ty: LLVMTypeRef, name: &str) -> LLVMValueRef {
+    let name = CString::new(name).unwrap();
+    unsafe { core::LLVMBuildPhi(builder, ty, name.as_ptr()) }
+}
+
+pub fn SetValueName(value: LLVMValueRef, name: &str) {
+    let name = CString::new(name).unwrap();
+    unsafe {
+        core::LLVMSetValueName(value, name.as_ptr())
+    }
+}
+
+pub fn GetValueName(value: LLVMValueRef) -> String {
+    unsafe { 
+        let name_ptr: *const c_char = core::LLVMGetValueName(value);
+        CStr::from_ptr(name_ptr).to_string_lossy().into_owned()
+    }
+}
+
+pub fn GetParams(function: LLVMValueRef) -> Vec<LLVMValueRef> {
+    let size = CountParams(function);
+    unsafe {
+        let mut container = Vec::with_capacity(size);
+        container.set_len(size);
+        core::LLVMGetParams(function, container.as_mut_ptr());
+        container
+    }
+}
+
+pub fn CountParams(function: LLVMValueRef) -> usize {
+    unsafe { core::LLVMCountParams(function) as usize }
+}
+
+pub fn BuildFCmp(builder: LLVMBuilderRef,
+                 op: LLVMRealPredicate,
+                 lhs: LLVMValueRef,
+                 rhs: LLVMValueRef,
+                 name: &str) -> LLVMValueRef {
+    let name = CString::new(name).unwrap();
+    unsafe { core::LLVMBuildFCmp(builder, op, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn BuildZExt(builder: LLVMBuilderRef,
+                       val: LLVMValueRef,
+                       dest_type: LLVMTypeRef,
+                       name: &str) -> LLVMValueRef {
+    let name = CString::new(name).unwrap();
+    unsafe { core::LLVMBuildZExt(builder, val, dest_type, name.as_ptr()) }
+}
+
+pub fn BuildUIToFP(builder: LLVMBuilderRef,
+                       val: LLVMValueRef,
+                       dest_type: LLVMTypeRef,
+                       name: &str) -> LLVMValueRef {
+
+    let name = CString::new(name).unwrap();
+    unsafe { core::LLVMBuildUIToFP(builder, val, dest_type, name.as_ptr()) }
+}
+
+pub fn BuildICmp(builder: LLVMBuilderRef,
+                 op: LLVMIntPredicate,
+                 lhs: LLVMValueRef,
+                 rhs: LLVMValueRef,
+                 name: &str) -> LLVMValueRef {
+    let name = CString::new(name).unwrap();
+    unsafe { core::LLVMBuildICmp(builder, op, lhs, rhs, name.as_ptr()) }
+}
+
+pub fn GetBasicBlockParent(block: LLVMBasicBlockRef) -> LLVMValueRef {
+    unsafe { core::LLVMGetBasicBlockParent(block) }
+}
+
+pub fn GetBasicBlocks(function: LLVMValueRef) -> Vec<LLVMBasicBlockRef> {
+    let size = CountBasicBlocks(function);
+    unsafe { 
+        let mut container = Vec::with_capacity(size);
+        container.set_len(size);
+        core::LLVMGetBasicBlocks(function, container.as_mut_ptr());
+        container
+    }
+}
+
+pub fn CountBasicBlocks(function: LLVMValueRef) -> usize {
+    unsafe { core::LLVMCountBasicBlocks(function) as usize }
+}
+
+pub fn PrintModuleToString(module: LLVMModuleRef) -> String {
+    unsafe {
+        let str_ptr: *const c_char = core::LLVMPrintModuleToString(module);
+        CStr::from_ptr(str_ptr).to_string_lossy().into_owned()
+    }
+}
+
+pub fn AddIncoming(phi_node: LLVMValueRef, mut incoming_values: Vec<LLVMValueRef>,
+                   mut incoming_blocks: Vec<LLVMBasicBlockRef>) {
+
+    let count = incoming_blocks.len() as u32;
+    if incoming_values.len() as u32 != count {
+        panic!("Bad invocation of AddIncoming");
+    }
+
+    unsafe {
+        let vals = incoming_values.as_mut_ptr();
+        let blocks = incoming_blocks.as_mut_ptr();
+        core::LLVMAddIncoming(phi_node, vals, blocks, count)
+    }
+}
+
+pub fn PrintModuleToFile(module: LLVMModuleRef, filename: &str) -> LLVMBool {
+    let out_file = CString::new(filename).unwrap();
+    unsafe { core::LLVMPrintModuleToFile(module, out_file.as_ptr(), ptr::null_mut()) }
+}

schala-repl/src/repl/command_tree.rs

@@ -1,99 +0,0 @@
-use super::{Repl, InterpreterDirectiveOutput};
-use crate::repl::directive_actions::DirectiveAction;
-use colored::*;
-
-/// A CommandTree is either a `Terminal` or a `NonTerminal`. When command parsing reaches the first
-/// Terminal, it will use the `DirectiveAction` found there to find an appropriate function to execute,
-/// and then execute it with any remaining arguments
-#[derive(Clone)]
-pub enum CommandTree {
-  Terminal {
-    name: String,
-    children: Vec<CommandTree>,
-    help_msg: Option<String>,
-    action: DirectiveAction,
-  },
-  NonTerminal {
-    name: String,
-    children: Vec<CommandTree>,
-    help_msg: Option<String>,
-    action: DirectiveAction,
-  },
-  Top(Vec<CommandTree>),
-}
-
-impl CommandTree {
-  pub fn nonterm_no_further_tab_completions(s: &str, help: Option<&str>) -> CommandTree {
-    CommandTree::NonTerminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children: vec![], action: DirectiveAction::Null }
-  }
-
-  pub fn terminal(s: &str, help: Option<&str>, children: Vec<CommandTree>, action: DirectiveAction) -> CommandTree {
-    CommandTree::Terminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), children, action}
-  }
-
-  pub fn nonterm(s: &str, help: Option<&str>, children: Vec<CommandTree>) -> CommandTree {
-    CommandTree::NonTerminal {
-      name: s.to_string(),
-      help_msg: help.map(|x| x.to_string()),
-      children,
-      action: DirectiveAction::Null
-    }
-  }
-
-  pub fn get_cmd(&self) -> &str {
-    match self {
-      CommandTree::Terminal { name, .. } => name.as_str(),
-      CommandTree::NonTerminal {name, ..} => name.as_str(),
-      CommandTree::Top(_) => "",
-    }
-  }
-  pub fn get_help(&self) -> &str {
-    match self {
-      CommandTree::Terminal { help_msg, ..} => help_msg.as_ref().map(|s| s.as_str()).unwrap_or(""),
-      CommandTree::NonTerminal { help_msg, .. } => help_msg.as_ref().map(|s| s.as_str()).unwrap_or(""),
-      CommandTree::Top(_) => ""
-    }
-  }
-  pub fn get_children(&self) -> &Vec<CommandTree> {
-    use CommandTree::*;
-    match self {
-      Terminal { children, .. } |
-      NonTerminal { children, .. } |
-      Top(children) => children
-    }
-  }
-  pub fn get_subcommands(&self) -> Vec<&str> {
-    self.get_children().iter().map(|x| x.get_cmd()).collect()
-  }
-
-  pub fn perform(&self, repl: &mut Repl, arguments: &Vec<&str>) -> InterpreterDirectiveOutput {
-    let mut dir_pointer: &CommandTree = self;
-    let mut idx = 0;
-
-    let res: Result<(DirectiveAction, usize), String> = loop {
-      match dir_pointer {
-        CommandTree::Top(subcommands) | CommandTree::NonTerminal { children: subcommands, .. } => {
-          let next_command = match arguments.get(idx) {
-            Some(cmd) => cmd,
-            None => break Err(format!("Command requires arguments"))
-          };
-          idx += 1;
-          match subcommands.iter().find(|sc| sc.get_cmd() == *next_command) {
-            Some(command_tree) => {
-              dir_pointer = command_tree;
-            },
-            None => break Err(format!("Command {} not found", next_command))
-          };
-        },
-        CommandTree::Terminal { action, .. } => {
-          break Ok((action.clone(), idx));
-        },
-      }
-    };
-
-    match res {
-      Ok((action, idx)) => action.perform(repl, &arguments[idx..]),
-      Err(err) => Some(err.red().to_string())
-    }
-  }
-}

schala-repl/src/repl/directive_actions.rs

@@ -1,133 +0,0 @@
-use super::{Repl, InterpreterDirectiveOutput};
-use crate::repl::help::help;
-use crate::language::{LangMetaRequest, LangMetaResponse, DebugAsk, DebugResponse}; 
-use itertools::Itertools;
-use std::fmt::Write as FmtWrite;
-
-#[derive(Debug, Clone)]
-pub enum DirectiveAction {
-  Null,
-  Help,
-  QuitProgram,
-  ListPasses,
-  ShowImmediate,
-  Show,
-  Hide,
-  TotalTimeOff,
-  TotalTimeOn,
-  StageTimeOff,
-  StageTimeOn,
-  Doc,
-}
-
-impl DirectiveAction {
-  pub fn perform(&self, repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-    use DirectiveAction::*;
-    match self {
-      Null => None,
-      Help => help(repl, arguments),
-      QuitProgram => {
-        repl.save_before_exit();
-        ::std::process::exit(0)
-      },
-      ListPasses => {
-        let language_state = repl.get_cur_language_state();
-        let pass_names = match language_state.request_meta(LangMetaRequest::StageNames) {
-          LangMetaResponse::StageNames(names) => names,
-          _ => vec![],
-        };
-
-        let mut buf = String::new();
-        for pass in pass_names.iter().map(|name| Some(name)).intersperse(None) {
-          match pass {
-            Some(pass) => write!(buf, "{}", pass).unwrap(),
-            None => write!(buf, " -> ").unwrap(),
-          }
-        }
-        Some(buf)
-      },
-      ShowImmediate => {
-        let cur_state = repl.get_cur_language_state();
-        let stage_name = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a thing to debug")),
-        };
-        let meta = LangMetaRequest::ImmediateDebug(DebugAsk::ByStage { stage_name: stage_name.clone(), token: None });
-        let meta_response = cur_state.request_meta(meta);
-
-        let response = match meta_response {
-          LangMetaResponse::ImmediateDebug(DebugResponse { ask, value }) => match  ask {
-            DebugAsk::ByStage { stage_name: ref this_stage_name, ..} if *this_stage_name == stage_name => value,
-            _ => return Some(format!("Wrong debug stage"))
-          },
-          _ => return Some(format!("Invalid language meta response")),
-        };
-        Some(response)
-      },
-      Show => {
-        let this_stage_name = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a stage to show")),
-        };
-        let token = arguments.get(1).map(|s| s.to_string());
-        repl.options.debug_asks.retain(|ask| match ask {
-          DebugAsk::ByStage { stage_name, .. } if *stage_name == this_stage_name => false,
-          _ => true
-        });
-
-        let ask = DebugAsk::ByStage { stage_name: this_stage_name, token };
-        repl.options.debug_asks.insert(ask);
-        None
-      },
-      Hide => {
-        let stage_name_to_remove = match arguments.get(0) {
-          Some(s) => s.to_string(),
-          None => return Some(format!("Must specify a stage to hide")),
-        };
-        repl.options.debug_asks.retain(|ask| match ask {
-          DebugAsk::ByStage { stage_name, .. } if *stage_name == stage_name_to_remove => false,
-          _ => true
-        });
-        None
-      },
-      TotalTimeOff => total_time_off(repl, arguments),
-      TotalTimeOn => total_time_on(repl, arguments),
-      StageTimeOff => stage_time_off(repl, arguments),
-      StageTimeOn => stage_time_on(repl, arguments),
-      Doc => doc(repl, arguments),
-    }
-  }
-}
-
-fn total_time_on(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_total_time = true;
-  None
-}
-
-fn total_time_off(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_total_time = false;
-  None
-}
-
-fn stage_time_on(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_stage_times = true;
-  None
-}
-
-fn stage_time_off(repl: &mut Repl, _: &[&str]) -> InterpreterDirectiveOutput {
-  repl.options.show_stage_times = false;
-  None
-}
-
-fn doc(repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-  arguments.get(0).map(|cmd| {
-    let source = cmd.to_string();
-    let meta = LangMetaRequest::Docs { source };
-    let cur_state = repl.get_cur_language_state();
-    match cur_state.request_meta(meta) {
-      LangMetaResponse::Docs { doc_string } => Some(doc_string),
-      _ => Some(format!("Invalid doc response"))
-    }
-  }).unwrap_or(Some(format!(":docs needs an argument")))
-}
-

schala-repl/src/repl/directives.rs

@@ -1,55 +0,0 @@
-use crate::repl::command_tree::CommandTree;
-use crate::repl::directive_actions::DirectiveAction;
-
-pub fn directives_from_pass_names(pass_names: &Vec<String>) -> CommandTree {
-  let passes_directives: Vec<CommandTree> = pass_names.iter()
-    .map(|pass_name| {
-      if pass_name == "parsing" {
-        CommandTree::nonterm(pass_name, None, vec![
-          CommandTree::nonterm_no_further_tab_completions("compact", None),
-          CommandTree::nonterm_no_further_tab_completions("expanded", None),
-          CommandTree::nonterm_no_further_tab_completions("trace", None),
-        ])
-      } else {
-        CommandTree::nonterm_no_further_tab_completions(pass_name, None) 
-      }
-    })
-    .collect();
-  CommandTree::Top(get_list(&passes_directives, true))
-}
-
-fn get_list(passes_directives: &Vec<CommandTree>, include_help: bool) -> Vec<CommandTree> {
-  use DirectiveAction::*;
-
-  vec![
-    CommandTree::terminal("exit", Some("exit the REPL"), vec![], QuitProgram),
-    CommandTree::terminal("quit", Some("exit the REPL"), vec![], QuitProgram),
-    CommandTree::terminal("help", Some("Print this help message"), if include_help { get_list(passes_directives, false) } else { vec![] }, Help),
-    CommandTree::nonterm("debug",
-      Some("Configure debug information"),
-      vec![
-        CommandTree::terminal("list-passes", Some("List all registered compiler passes"), vec![], ListPasses),
-        CommandTree::terminal("show-immediate", None, passes_directives.clone(), ShowImmediate),
-        CommandTree::terminal("show", Some("Show debug output for a specific pass"), passes_directives.clone(), Show),
-        CommandTree::terminal("hide", Some("Hide debug output for a specific pass"), passes_directives.clone(), Hide),
-        CommandTree::nonterm("total-time", None, vec![
-          CommandTree::terminal("on", None, vec![], TotalTimeOn), 
-          CommandTree::terminal("off", None, vec![], TotalTimeOff),
-        ]),
-        CommandTree::nonterm("stage-times", Some("Computation time per-stage"), vec![
-          CommandTree::terminal("on", None, vec![], StageTimeOn),
-          CommandTree::terminal("off", None, vec![], StageTimeOff),
-        ])
-      ]
-    ),
-    CommandTree::nonterm("lang",
-      Some("switch between languages, or go directly to a langauge by name"),
-      vec![
-        CommandTree::nonterm_no_further_tab_completions("next", None),
-        CommandTree::nonterm_no_further_tab_completions("prev", None),
-        CommandTree::nonterm("go", None, vec![]),
-      ]
-    ),
-    CommandTree::terminal("doc", Some("Get language-specific help for an item"), vec![], Doc),
-  ]
-}

schala-repl/src/repl/help.rs

@@ -1,54 +0,0 @@
-use std::fmt::Write as FmtWrite;
-
-use colored::*;
-use super::command_tree::CommandTree;
-use super::{Repl, InterpreterDirectiveOutput};
-
-pub fn help(repl: &mut Repl, arguments: &[&str]) -> InterpreterDirectiveOutput {
-  match arguments {
-    [] =>  return global_help(repl),
-    commands => {
-      let dirs = repl.get_directives();
-      Some(match get_directive_from_commands(commands, &dirs) {
-        None => format!("Directive `{}` not found", commands.last().unwrap()),
-        Some(dir) => {
-          let mut buf = String::new();
-          writeln!(buf, "`{}` - {}", dir.get_cmd(), dir.get_help()).unwrap();
-          buf
-        }
-      })
-    }
-  }
-}
-
-fn get_directive_from_commands<'a>(commands: &[&str], dirs: &'a CommandTree) -> Option<&'a CommandTree> {
-  let mut directive_list = dirs.get_children();
-  let mut matched_directive = None;
-  for cmd in commands {
-    let found = directive_list.iter().find(|directive| directive.get_cmd() == *cmd);
-    if let Some(dir) = found {
-      directive_list = dir.get_children();
-    }
-
-    matched_directive = found;
-  }
-  matched_directive
-}
-
-fn global_help(repl: &mut Repl) -> InterpreterDirectiveOutput {
-  let mut buf = String::new();
-  let sigil = repl.interpreter_directive_sigil;
-
-  writeln!(buf, "{} version {}", "Schala REPL".bright_red().bold(), crate::VERSION_STRING).unwrap();
-  writeln!(buf, "-----------------------").unwrap();
-
-  for directive in repl.get_directives().get_children() {
-    writeln!(buf, "{}{} - {}", sigil, directive.get_cmd(), directive.get_help()).unwrap();
-  }
-
-  let ref lang = repl.get_cur_language_state();
-  writeln!(buf, "").unwrap();
-  writeln!(buf, "Language-specific help for {}", lang.get_language_name()).unwrap();
-  writeln!(buf, "-----------------------").unwrap();
-  Some(buf)
-}

schala-repl/src/repl/mod.rs

@@ -1,209 +0,0 @@
-use std::sync::Arc;
-use std::collections::HashSet;
-
-use crate::language::{ProgrammingLanguageInterface,
-ComputationRequest, LangMetaResponse, LangMetaRequest};
-
-mod command_tree;
-use self::command_tree::CommandTree;
-mod repl_options;
-use repl_options::ReplOptions;
-mod directive_actions;
-mod directives;
-use directives::directives_from_pass_names;
-mod help;
-mod response;
-use response::ReplResponse;
-
-const HISTORY_SAVE_FILE: &'static str = ".schala_history";
-const OPTIONS_SAVE_FILE: &'static str = ".schala_repl";
-
-type InterpreterDirectiveOutput = Option<String>;
-
-pub struct Repl {
-  pub interpreter_directive_sigil: char,
-  line_reader: ::linefeed::interface::Interface<::linefeed::terminal::DefaultTerminal>,
-  language_states: Vec<Box<dyn ProgrammingLanguageInterface>>,
-  options: ReplOptions,
-}
-
-impl Repl {
-  pub fn new(initial_states: Vec<Box<dyn ProgrammingLanguageInterface>>) -> Repl {
-    use linefeed::Interface;
-    let line_reader = Interface::new("schala-repl").unwrap();
-    let interpreter_directive_sigil = ':';
-
-    Repl {
-      interpreter_directive_sigil,
-      line_reader,
-      language_states: initial_states,
-      options: ReplOptions::new(),
-    }
-  }
-
-  pub fn run_repl(&mut self) {
-    println!("Schala MetaInterpreter version {}", crate::VERSION_STRING);
-    println!("Type {}help for help with the REPL", self.interpreter_directive_sigil);
-    self.load_options();
-    self.handle_repl_loop();
-    self.save_before_exit();
-    println!("Exiting...");
-  }
-
-  fn load_options(&mut self) {
-    self.line_reader.load_history(HISTORY_SAVE_FILE).unwrap_or(());
-    match ReplOptions::load_from_file(OPTIONS_SAVE_FILE) {
-      Ok(options) => {
-        self.options = options;
-      },
-      Err(()) => ()
-    };
-  }
-
-  fn handle_repl_loop(&mut self) {
-    use linefeed::ReadResult::*;
-
-    loop {
-      self.update_line_reader();
-      match self.line_reader.read_line() {
-        Err(e) => {
-          println!("readline IO Error: {}", e);
-          break;
-        },
-        Ok(Eof) | Ok(Signal(_)) => break,
-        Ok(Input(ref input)) => {
-          self.line_reader.add_history_unique(input.to_string());
-          match input.chars().nth(0) {
-            Some(ch) if ch == self.interpreter_directive_sigil => match self.handle_interpreter_directive(input) {
-              Some(directive_output) => println!("<> {}", directive_output),
-              None => (),
-            },
-            _ => {
-              for repl_response in self.handle_input(input) {
-                println!("{}", repl_response);
-              }
-            }
-          }
-        }
-      }
-    }
-  }
-
-  fn update_line_reader(&mut self) {
-    let tab_complete_handler = TabCompleteHandler::new(self.interpreter_directive_sigil, self.get_directives());
-    self.line_reader.set_completer(Arc::new(tab_complete_handler)); //TODO fix this here
-    let prompt_str = format!(">> ");
-    self.line_reader.set_prompt(&prompt_str).unwrap();
-  }
-
-  fn save_before_exit(&self) {
-    self.line_reader.save_history(HISTORY_SAVE_FILE).unwrap_or(());
-    self.options.save_to_file(OPTIONS_SAVE_FILE);
-  }
-
-  fn handle_interpreter_directive(&mut self, input: &str) -> InterpreterDirectiveOutput {
-    let mut iter = input.chars();
-    iter.next();
-    let arguments: Vec<&str> = iter
-      .as_str()
-      .split_whitespace()
-      .collect();
-
-    if arguments.len() < 1 {
-      return None;
-    }
-
-    let directives = self.get_directives();
-    directives.perform(self, &arguments)
-  }
-
-  fn get_cur_language_state(&mut self) -> &mut Box<dyn ProgrammingLanguageInterface> {
-    //TODO this is obviously not complete
-    &mut self.language_states[0]
-  }
-
-  fn handle_input(&mut self, input: &str) -> Vec<ReplResponse> {
-    let mut debug_requests = HashSet::new();
-    for ask in self.options.debug_asks.iter() {
-      debug_requests.insert(ask.clone());
-    }
-
-    let request = ComputationRequest { source: input, debug_requests };
-    let ref mut language_state = self.get_cur_language_state();
-    let response = language_state.run_computation(request);
-    response::handle_computation_response(response, &self.options)
-  }
-
-  fn get_directives(&mut self) -> CommandTree {
-    let language_state = self.get_cur_language_state();
-    let pass_names = match language_state.request_meta(LangMetaRequest::StageNames) {
-      LangMetaResponse::StageNames(names) => names,
-      _ => vec![],
-    };
-
-    directives_from_pass_names(&pass_names)
-  }
-}
-
-
-struct TabCompleteHandler {
-  sigil: char,
-  top_level_commands: CommandTree,
-}
-
-use linefeed::complete::{Completion, Completer};
-use linefeed::terminal::Terminal;
-
-impl TabCompleteHandler {
-  fn new(sigil: char, top_level_commands: CommandTree) -> TabCompleteHandler {
-    TabCompleteHandler {
-      top_level_commands,
-      sigil,
-    }
-  }
-}
-
-impl<T: Terminal> Completer<T> for TabCompleteHandler {
-  fn complete(&self, word: &str, prompter: &::linefeed::prompter::Prompter<T>, start: usize, _end: usize) -> Option<Vec<Completion>> {
-    let line = prompter.buffer();
-
-    if !line.starts_with(self.sigil) {
-      return None;
-    }
-
-    let mut words = line[1..(if start == 0 { 1 } else { start })].split_whitespace();
-    let mut completions = Vec::new();
-    let mut command_tree: Option<&CommandTree> = Some(&self.top_level_commands);
-
-    loop {
-      match words.next() {
-        None => {
-          let top = match command_tree {
-            Some(CommandTree::Top(_)) => true,
-            _ => false
-          };
-          let word = if top { word.get(1..).unwrap() } else { word };
-          for cmd in command_tree.map(|x| x.get_subcommands()).unwrap_or(vec![]).into_iter() {
-            if cmd.starts_with(word) {
-              completions.push(Completion {
-                completion: format!("{}{}", if top { ":" } else { "" }, cmd),
-                display: Some(cmd.to_string()),
-                suffix: ::linefeed::complete::Suffix::Some(' ')
-              })
-            }
-          }
-          break;
-        },
-        Some(s) => {
-          let new_ptr: Option<&CommandTree> = command_tree.and_then(|cm| match cm {
-            CommandTree::Top(children) => children.iter().find(|c| c.get_cmd() == s),
-            CommandTree::NonTerminal { children, .. } => children.iter().find(|c| c.get_cmd() == s),
-            CommandTree::Terminal { children, .. } => children.iter().find(|c| c.get_cmd() == s),
-          });
-          command_tree = new_ptr;
-        }
-      }
-    }
-    Some(completions)
-  }
-}

schala-repl/src/repl/repl_options.rs

@@ -1,47 +0,0 @@
-use crate::language::DebugAsk;
-
-use std::io::{Read, Write};
-use std::collections::HashSet;
-use std::fs::File;
-
-#[derive(Serialize, Deserialize)]
-pub struct ReplOptions {
-  pub debug_asks: HashSet<DebugAsk>,
-  pub show_total_time: bool,
-  pub show_stage_times: bool,
-}
-
-impl ReplOptions {
-  pub fn new() -> ReplOptions {
-    ReplOptions {
-      debug_asks: HashSet::new(),
-      show_total_time: true,
-      show_stage_times: false,
-    }
-  }
-
-  pub fn save_to_file(&self, filename: &str) {
-    let res = File::create(filename)
-      .and_then(|mut file| {
-        let buf = crate::serde_json::to_string(self).unwrap();
-        file.write_all(buf.as_bytes())
-      });
-    if let Err(err) = res {
-      println!("Error saving {} file {}", filename, err);
-    }
-  }
-
-  pub fn load_from_file(filename: &str) -> Result<ReplOptions, ()> {
-    File::open(filename)
-      .and_then(|mut file| {
-        let mut contents = String::new();
-        file.read_to_string(&mut contents)?;
-        Ok(contents)
-      })
-    .and_then(|contents| {
-      let output: ReplOptions = crate::serde_json::from_str(&contents)?;
-      Ok(output)
-    })
-    .map_err(|_| ())
-  }
-}

schala-repl/src/repl/response.rs

@@ -1,67 +0,0 @@
-use colored::*;
-use std::fmt;
-use std::fmt::Write;
-
-use super::ReplOptions;
-use crate::language::{ DebugAsk, ComputationResponse};
-
-pub struct ReplResponse {
-  label: Option<String>,
-  text: String,
-  color: Option<Color>
-}
-
-impl fmt::Display for ReplResponse {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let mut buf = String::new();
-    if let Some(ref label) = self.label {
-      write!(buf, "({})", label).unwrap();
-    }
-    write!(buf, "=> {}", self.text).unwrap();
-    write!(f, "{}", match self.color {
-      Some(c) => buf.color(c),
-      None => buf.normal()
-    })
-  }
-}
-
-
-pub fn handle_computation_response(response: ComputationResponse, options: &ReplOptions) -> Vec<ReplResponse> {
-  let mut responses = vec![];
-
-  if options.show_total_time {
-    responses.push(ReplResponse {
-      label: Some("Total time".to_string()),
-      text: format!("{:?}", response.global_output_stats.total_duration),
-      color: None,
-    });
-  }
-
-  if options.show_stage_times {
-    responses.push(ReplResponse {
-      label: Some("Stage times".to_string()),
-      text: format!("{:?}", response.global_output_stats.stage_durations),
-      color: None,
-    });
-  }
-
-  for debug_resp in response.debug_responses {
-    let stage_name = match debug_resp.ask {
-      DebugAsk::ByStage { stage_name, .. } => stage_name,
-      _ => continue,
-    };
-    responses.push(ReplResponse {
-      label: Some(stage_name.to_string()),
-      text: debug_resp.value,
-      color: Some(Color::Red),
-    });
-  }
-
-  responses.push(match response.main_output {
-    Ok(s) => ReplResponse { label: None, text: s, color: None },
-    Err(e) => ReplResponse { label: Some("Error".to_string()), text: e, color: Some(Color::Red) },
-  });
-
-  responses
-}
-

schala-repl/src/webapp.rs

@@ -0,0 +1,44 @@
+use rocket;
+use rocket::State;
+use rocket::response::Content;
+use rocket::http::ContentType;
+use rocket_contrib::Json;
+use language::{ProgrammingLanguageInterface, EvalOptions};
+use WEBFILES;
+use ::PLIGenerator;
+
+#[get("/")]
+fn index() -> Content<String> {
+  let path = "static/index.html";
+  let html_contents = String::from_utf8(WEBFILES.get(path).unwrap().into_owned()).unwrap();
+  Content(ContentType::HTML, html_contents)
+}
+
+#[get("/bundle.js")]
+fn js_bundle() -> Content<String> {
+  let path = "static/bundle.js";
+  let js_contents = String::from_utf8(WEBFILES.get(path).unwrap().into_owned()).unwrap();
+  Content(ContentType::JavaScript, js_contents)
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Input {
+  source: String,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Output {
+  text: String,
+}
+
+#[post("/input", format = "application/json", data = "<input>")]
+fn interpreter_input(input: Json<Input>, generators: State<Vec<PLIGenerator>>) -> Json<Output> {
+  let schala_gen = generators.get(0).unwrap();
+  let mut schala: Box<ProgrammingLanguageInterface> = schala_gen();
+  let code_output = schala.execute_pipeline(&input.source, &EvalOptions::default());
+  Json(Output { text: code_output.to_repl() })
+}
+
+pub fn web_main(language_generators: Vec<PLIGenerator>) {
+  rocket::ignite().manage(language_generators).mount("/", routes![index, js_bundle, interpreter_input]).launch();
+}

src/main.rs

@@ -1,15 +1,20 @@
 extern crate schala_repl;
 
-//extern crate maaru_lang;
-//extern crate rukka_lang;
-//extern crate robo_lang;
+extern crate maaru_lang;
+extern crate rukka_lang;
+extern crate robo_lang;
 extern crate schala_lang;
-use schala_repl::{ProgrammingLanguageInterface, start_repl};
+use schala_repl::{PLIGenerator, repl_main};
 
 extern { }
 
 fn main() {
-  let langs: Vec<Box<dyn ProgrammingLanguageInterface>> = vec![Box::new(schala_lang::Schala::new())];
-  start_repl(langs);
+  let generators: Vec<PLIGenerator> = vec![
+    Box::new(|| { Box::new(schala_lang::Schala::new())}),
+    Box::new(|| { Box::new(maaru_lang::Maaru::new())}),
+    Box::new(|| { Box::new(robo_lang::Robo::new())}),
+    Box::new(|| { Box::new(rukka_lang::Rukka::new())}),
+  ];
+  repl_main(generators);
 }