A solution for multiline entry

I don't really like this...

.gitignore

@@ -1,3 +1,4 @@
+Cargo.lock
 target
 .schala_repl
 .schala_history

Cargo.toml

@@ -6,10 +6,12 @@ authors = ["greg <greg.shuflin@protonmail.com>"]
 [dependencies]
 
 schala-repl = { path = "schala-repl" }
+schala-repl-codegen = { path = "schala-repl-codegen" }
+maaru-lang = { path = "maaru" }
+rukka-lang = { path = "rukka" }
+robo-lang = { path = "robo" }
 schala-lang = { path = "schala-lang/language" }
-# maaru-lang = { path = "maaru" }
-# rukka-lang = { path = "rukka" }
-# robo-lang = { path = "robo" }
+schala-lang-codegen = { path = "schala-lang/codegen" }
 
 [build-dependencies]
 includedir_codegen = "0.2.0"

README.md

@@ -1,22 +1,19 @@
 # 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
+with 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.
+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. 
+function `repl_main` meant to be used as the equivalent of main() for library
+users. This function parses command-line arguments and either runs an interactive
+REPL or interprets a program non-interactively.
 
-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.
+Individual programming language implementations are Rust types that implement
+the `ProgrammingLanguageInterface` trait and store whatever persistent state is
+relevant to that language. The ability to share state between different
+programming languages is in the works.
 
 ## History
 
@@ -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
@@ -59,22 +56,12 @@ 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
 

TODO.md

@@ -1,146 +1,58 @@
-# Plan of attack
+#Typechecking Notes
 
--ONLY two types of statement, Expressoin and Declaration
--modules and imports are just types of Declarables
-
-1. modify visitor so it can handle scopes
-  -this is needed both to handle import scope correctly
-  -and also to support making FQSNs aware of function parameters
-
-2. Once FQSNs are aware of function parameters, most of the Rc<String> things in eval.rs can go away
-
-# TODO items
-
--use 'let' sigil in patterns for variables :
-
-```
-  q is MyStruct(let a, Chrono::Trigga) then {
+(cf. cardelli paper)
 
+Given a length function def:
+````
+fn length(x) {
+ if x.is_null {
+   0
+  } else {
+   succ(length(x.tail))
   }
-```
+}
+````
+Constraints:
+.null: List a -> bool
+.tail: List a -> List a
+0: Nat
+succ: Nat -> Nat
 
--idea: what if there was something like React jsx syntas built in? i.e. a way to automatically transform some kind of markup
-into a function call, cf. `<h1 prop="arg">` ->  h1(prop=arg)
 
-## General code cleanup
-- I think I can restructure the parser to get rid of most instances of expect!, at least at the beginning of a rule
-DONE -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
-  - maybe implement this twice: 1) the value-returning, no-default one in the haoyi blogpost,
-  -look at https://gitlab.haskell.org/ghc/ghc/wikis/pattern-synonyms
-                                2) the non-value-returning, default one like in rustc (cf. https://github.com/rust-unofficial/patterns/blob/master/patterns/visitor.md)
 
--parser error - should report subset of AST parsed *so far*
-  - what if you used python 'def' syntax to define a function? what error message makes sense here?
 
-## Reduction
- - make a good type for actual language builtins to avoid string comparisons
+# TODO Items
 
-## Typechecking
+-make the REPL more advanced!
 
-- make a type to represent types rather than relying on string comparisons
+-Plan of attack:
+  -write a visitor pattern for AST
+  -convert AST type to including SourceMap'd wrappers (w/ .into())
+    -at the same time, amke sure the visitor pattern "skips over" the SourceMap'd stuff
+    so it can just care about AST structure
 
-- look at https://rickyhan.com/jekyll/update/2018/05/26/hindley-milner-tutorial-rust.html
+- 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
 
-- 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
+-scala-style html"dfasfsadf${}" string interpolations!
 
-- think about idris-related ideas of multiple implementations of a type for an interface (+ vs * impl for monoids, for preorder/inorder/postorder for Foldable)
+-fuzz test schala
 
--should have an Idris-like `cast To From` function
+-look into Inkwell for LLVM
 
-## 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
 
-
-## Trying if-syntax again
-
-//simple if expr
-if x == 10 then "a" else "z"
-
-//complex if expr
-if x == 10 then {
-  let a = 1
-  let b = 2
-  a + b
-} else {
-  55
-}
-
-// different comparison ops
-if x {
- == 1 then "a"
-  .isPrime() then "b"
-  else "c"
-}
-
-/* for now disallow `if x == { 1 then ... }`, b/c hard to parse
-
-//simple pattern-matching
-if x is Person("Ivan", age) then age else 0
-
-//match-block equivalent
-if x {
- is Person("Ivan", _) then "Ivan"
- is Person(_, age) if age > 13 then "barmitzvah'd"
- else "foo"
- }
-
-
-
-## (OLD) Playing around with conditional syntax ideas
-
-
 - if/match playground
 
 simple if
@@ -179,3 +91,67 @@ 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
+
+
+
+
+
+*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/lib.rs

@@ -6,6 +6,8 @@ mod tokenizer;
 mod parser;
 mod eval;
 
+use schala_repl::{ProgrammingLanguageInterface, EvalOptions, UnfinishedComputation, FinishedComputation, TraceArtifact};
+
 #[derive(Debug)]
 pub struct TokenError {
     pub msg: String,
@@ -31,42 +33,6 @@ 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 +40,37 @@ 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))
+  }
 }
-  */

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-lang/codegen/src/lib.rs

@@ -32,11 +32,7 @@ impl Fold for RecursiveDescentFn {
         if self.parse_level != 0 {
           self.parse_level -= 1;
         }
-
-        result.map_err(|mut parse_error: ParseError| {
-          parse_error.production_name = Some(stringify!(#ident).to_string());
-          parse_error
-        })
+        result
       }
     };
     i.block = Box::new(new_block);

schala-lang/language/Cargo.toml

@@ -5,17 +5,13 @@ 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"
-colored = "1.8"
-radix_trie = "0.1.5"
-nom = "5.1.0"
+itertools = "0.5.8"
+take_mut = "0.1.3"
+maplit = "*"
+lazy_static = "0.2.8"
+failure = "0.1.2"
+
 
 schala-lang-codegen = { path = "../codegen" }
 schala-repl = { path = "../../schala-repl" }
+schala-repl-codegen = { path = "../../schala-repl-codegen" }

schala-lang/language/src/ast.rs

@@ -1,90 +1,47 @@
 use std::rc::Rc;
+use std::convert::From;
 
-use crate::derivative::Derivative;
+use crate::builtin::{BinOp, PrefixOp};
 
-mod walker;
-mod visitor;
-mod visitor_test;
-mod operators;
-pub use operators::*;
-pub use visitor::ASTVisitor;
-pub use walker::walk_ast;
-
-/// An abstract identifier for an AST node
-#[derive(Debug, PartialEq, Eq, Hash, Clone)]
-pub struct ItemId {
-  idx: u32,
+#[derive(Clone, Debug, PartialEq)]
+pub struct Node<T> {
+  n: T,
+  source_map: SourceMap
 }
 
-impl ItemId {
-  pub fn new(n: u32) -> ItemId {
-    ItemId { idx: n }
+impl<T> Node<T> {
+  pub fn new(n: T) -> Node<T> {
+    Node { n, source_map: SourceMap::default() }
+  }
+
+  pub fn node(&self) -> &T {
+    &self.n
   }
 }
 
-pub struct ItemIdStore {
-  last_idx: u32
+//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 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)
+impl From<Expression> for Node<Expression> {
+  fn from(expr: Expression) -> Node<Expression> {
+    Node { n: expr, source_map: SourceMap::default() }
   }
 }
 
-#[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)]
+pub struct AST(pub Vec<Node<Statement>>);
 
 #[derive(Debug, PartialEq, Clone)]
-pub enum StatementKind {
-  Expression(Expression),
+pub enum Statement {
+  ExpressionStatement(Node<Expression>),
   Declaration(Declaration),
-  Import(ImportSpecifier),
-  Module(ModuleSpecifier),
 }
 
-pub type Block = Vec<Statement>;
+pub type Block = Vec<Node<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>
-}
+pub type FormalParam = (ParamName, Option<TypeIdentifier>);
 
 #[derive(Debug, PartialEq, Clone)]
 pub enum Declaration {
@@ -95,15 +52,10 @@ pub enum Declaration {
     body: TypeBody,
     mutable: bool
   },
-  //TODO this needs to be more sophisticated
-  TypeAlias {
-    alias: Rc<String>,
-    original: Rc<String>,
-  },
+  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 {
@@ -138,24 +90,9 @@ pub enum Variant {
   }
 }
 
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct Expression {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub kind: ExpressionKind,
-  pub type_anno: Option<TypeIdentifier>
-}
+#[derive(Debug, PartialEq, Clone)]
+pub struct Expression(pub ExpressionType, pub 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 {
@@ -170,29 +107,29 @@ pub struct TypeSingletonName {
 }
 
 #[derive(Debug, PartialEq, Clone)]
-pub enum ExpressionKind {
+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(QualifiedName),
+  BinExp(BinOp, Box<Node<Expression>>, Box<Node<Expression>>),
+  PrefixExp(PrefixOp, Box<Node<Expression>>),
+  TupleLiteral(Vec<Node<Expression>>),
+  Value(Rc<String>),
   NamedStruct {
-    name: QualifiedName,
+    name: Rc<String>,
     fields: Vec<(Rc<String>, Expression)>,
   },
   Call {
     f: Box<Expression>,
-    arguments: Vec<InvocationArgument>,
+    arguments: Vec<Node<Expression>>,
   },
   Index {
     indexee: Box<Expression>,
     indexers: Vec<Expression>,
   },
   IfExpression {
-    discriminator: Option<Box<Expression>>,
+    discriminator: Box<Discriminator>,
     body: Box<IfExpressionBody>,
   },
   WhileExpression {
@@ -212,42 +149,34 @@ pub enum ExpressionKind {
 }
 
 #[derive(Debug, PartialEq, Clone)]
-pub enum InvocationArgument {
-  Positional(Expression),
-  Keyword {
-    name: Rc<String>,
-    expr: Expression,
-  },
-  Ignored
+pub enum Discriminator {
+  Simple(Expression),
+  BinOp(Expression, BinOp)
 }
 
 #[derive(Debug, PartialEq, Clone)]
 pub enum IfExpressionBody {
-  SimpleConditional {
-    then_case: Block,
-    else_case: Option<Block>
-  },
-  SimplePatternMatch {
-    pattern: Pattern,
-    then_case: Block,
-    else_case: Option<Block>
-  },
-  CondList(Vec<ConditionArm>)
+  SimpleConditional(Block, Option<Block>),
+  SimplePatternMatch(Pattern, Block, Option<Block>),
+  GuardList(Vec<GuardArm>)
 }
 
 #[derive(Debug, PartialEq, Clone)]
-pub struct ConditionArm {
-  pub condition: Condition,
-  pub guard: Option<Expression>,
+pub struct GuardArm {
+  pub guard: Guard,
   pub body: Block,
 }
 
 #[derive(Debug, PartialEq, Clone)]
-pub enum Condition {
-  Pattern(Pattern),
-  TruncatedOp(BinOp, Expression),
-  Expression(Expression),
-  Else,
+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)]
@@ -255,19 +184,19 @@ pub enum Pattern {
   Ignored,
   TuplePattern(Vec<Pattern>),
   Literal(PatternLiteral),
-  TupleStruct(QualifiedName, Vec<Pattern>),
-  Record(QualifiedName, Vec<(Rc<String>, Pattern)>),
-  VarOrName(QualifiedName),
+  TupleStruct(Rc<String>, Vec<Pattern>),
+  Record(Rc<String>, Vec<(Rc<String>, Pattern)>),
 }
 
 #[derive(Debug, PartialEq, Clone)]
 pub enum PatternLiteral {
   NumPattern {
     neg: bool,
-    num: ExpressionKind,
+    num: ExpressionType,
   },
   StringPattern(Rc<String>),
   BoolPattern(bool),
+  VarPattern(Rc<String>)
 }
 
 #[derive(Debug, PartialEq, Clone)]
@@ -281,27 +210,3 @@ pub enum ForBody {
   MonadicReturn(Expression),
   StatementBlock(Block),
 }
-
-#[derive(Debug, Derivative, Clone)]
-#[derivative(PartialEq)]
-pub struct ImportSpecifier {
-  #[derivative(PartialEq="ignore")]
-  pub id: ItemId,
-  pub path_components: Vec<Rc<String>>,
-  pub imported_names: ImportedNames
-}
-
-#[derive(Debug, PartialEq, Clone)]
-pub enum ImportedNames {
-  All,
-  LastOfPath,
-  List(Vec<Rc<String>>)
-}
-
-
-#[derive(Debug, PartialEq, Clone)]
-pub struct ModuleSpecifier {
-  pub name: Rc<String>,
-  pub contents: Vec<Statement>,
-}
-

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 precedence(&self) -> i32 {
-    binop_precedences(self.sigil.as_str())
-  }
-}
-
-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/ast/visitor.rs

@@ -1,41 +0,0 @@
-use std::rc::Rc;
-use crate::ast::*;
-
-//TODO maybe these functions should take closures that return a KeepRecursing | StopHere type,
-//or a tuple of (T, <that type>)
-
-pub trait ASTVisitor: Sized {
-  fn ast(&mut self, _ast: &AST) {}
-  fn block(&mut self, _statements: &Vec<Statement>) {}
-  fn statement(&mut self, _statement: &Statement) {}
-  fn declaration(&mut self, _declaration: &Declaration) {}
-  fn signature(&mut self, _signature: &Signature) {}
-  fn type_declaration(&mut self, _name: &TypeSingletonName, _body: &TypeBody, _mutable: bool) {}
-  fn type_alias(&mut self, _alias: &Rc<String>, _original: &Rc<String>) {}
-  fn binding(&mut self, _name: &Rc<String>, _constant: bool, _type_anno: Option<&TypeIdentifier>, _expr: &Expression) {}
-  fn implemention(&mut self, _type_name: &TypeIdentifier, _interface_name: Option<&TypeSingletonName>, _block: &Vec<Declaration>) {}
-  fn interface(&mut self, _name: &Rc<String>, _signatures: &Vec<Signature>) {}
-  fn expression(&mut self, _expression: &Expression) {}
-  fn expression_kind(&mut self, _kind: &ExpressionKind) {}
-  fn type_annotation(&mut self, _type_anno: Option<&TypeIdentifier>) {}
-  fn named_struct(&mut self, _name: &QualifiedName, _fields: &Vec<(Rc<String>, Expression)>) {}
-  fn call(&mut self, _f: &Expression, _arguments: &Vec<InvocationArgument>) {}
-  fn index(&mut self, _indexee: &Expression, _indexers: &Vec<Expression>) {}
-  fn if_expression(&mut self, _discrim: Option<&Expression>, _body: &IfExpressionBody) {}
-  fn condition_arm(&mut self, _arm: &ConditionArm) {}
-  fn while_expression(&mut self, _condition: Option<&Expression>, _body: &Block) {}
-  fn for_expression(&mut self, _enumerators: &Vec<Enumerator>, _body: &ForBody) {}
-  fn lambda(&mut self, _params: &Vec<FormalParam>, _type_anno: Option<&TypeIdentifier>, _body: &Block) {}
-  fn invocation_argument(&mut self, _arg: &InvocationArgument) {}
-  fn formal_param(&mut self, _param: &FormalParam) {}
-  fn import(&mut self, _import: &ImportSpecifier) {}
-  fn module(&mut self, _module: &ModuleSpecifier) {}
-  fn qualified_name(&mut self, _name: &QualifiedName) {}
-  fn nat_literal(&mut self, _n: u64) {}
-  fn float_literal(&mut self, _f: f64) {}
-  fn string_literal(&mut self, _s: &Rc<String>) {}
-  fn bool_literal(&mut self, _b: bool) {}
-  fn binexp(&mut self, _op: &BinOp, _lhs: &Expression, _rhs: &Expression) {}
-  fn prefix_exp(&mut self, _op: &PrefixOp, _arg: &Expression) {}
-  fn pattern(&mut self, _pat: &Pattern) {}
-}

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

@@ -1,41 +0,0 @@
-#![cfg(test)]
-
-use crate::ast::visitor::ASTVisitor;
-use crate::ast::walker;
-use crate::util::quick_ast;
-
-struct Tester {
-  count: u64,
-  float_count: u64
-}
-
-impl ASTVisitor for Tester {
-  fn nat_literal(&mut self, _n: u64) {
-    self.count += 1;
-  }
-  fn float_literal(&mut self, _f: f64) {
-    self.float_count += 1;
-  }
-}
-
-
-#[test]
-fn foo() {
-  let mut tester = Tester { count: 0, float_count: 0 };
-  let (ast, _) = quick_ast(r#"
-import gragh
-
-let a = 20 + 84
-let b = 28 + 1 + 2 + 2.0
-fn heh() {
-  let m = 9
-
-}
-
-"#);
-
-  walker::walk_ast(&mut tester, &ast);
-
-  assert_eq!(tester.count, 6);
-  assert_eq!(tester.float_count, 1);
-}

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

@@ -1,269 +0,0 @@
-#![allow(dead_code)]
-use std::rc::Rc;
-use crate::ast::*;
-use crate::ast::visitor::ASTVisitor;
-use crate::util::deref_optional_box;
-
-pub fn walk_ast<V: ASTVisitor>(v: &mut V, ast: &AST) {
-  v.ast(ast);
-  walk_block(v, &ast.statements);
-}
-
-fn walk_block<V: ASTVisitor>(v: &mut V, block: &Vec<Statement>) {
-  for s in block {
-    v.statement(s);
-    statement(v, s);
-  }
-}
-
-fn statement<V: ASTVisitor>(v: &mut V, statement: &Statement) {
-  use StatementKind::*;
-  match statement.kind {
-    Expression(ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Declaration(ref decl) => {
-      v.declaration(decl);
-      declaration(v, decl);
-    },
-    Import(ref import_spec) => v.import(import_spec),
-    Module(ref module_spec) => {
-      v.module(module_spec);
-      walk_block(v, &module_spec.contents);
-    }
-  }
-}
-
-fn declaration<V: ASTVisitor>(v: &mut V, decl: &Declaration) {
-  use Declaration::*;
-  match decl {
-    FuncSig(sig) => {
-      v.signature(&sig);
-      signature(v, &sig);
-    },
-    FuncDecl(sig, block) => {
-      v.signature(&sig);
-      v.block(&block);
-      walk_block(v, block);
-    },
-    TypeDecl { name, body, mutable  } => v.type_declaration(name, body, *mutable),
-    TypeAlias { alias, original} => v.type_alias(alias, original), 
-    Binding { name, constant, type_anno, expr } => {
-      v.binding(name, *constant, type_anno.as_ref(), expr);
-      v.type_annotation(type_anno.as_ref());
-      v.expression(&expr);
-      expression(v, &expr);
-    },
-    Impl { type_name, interface_name, block } => {
-      v.implemention(type_name, interface_name.as_ref(), block);
-    }
-    Interface { name, signatures } => v.interface(name, signatures),
-  }
-}
-
-fn signature<V: ASTVisitor>(v: &mut V, signature: &Signature) {
-  for p in signature.params.iter() {
-    v.formal_param(p);
-  }
-  v.type_annotation(signature.type_anno.as_ref());
-  for p in signature.params.iter() {
-    formal_param(v, p);
-  }
-}
-
-fn expression<V: ASTVisitor>(v: &mut V, expression: &Expression) {
-  v.expression_kind(&expression.kind);
-  v.type_annotation(expression.type_anno.as_ref());
-  expression_kind(v, &expression.kind);
-}
-
-
-fn call<V: ASTVisitor>(v: &mut V, f: &Expression, args: &Vec<InvocationArgument>) {
-  v.expression(f);
-  expression(v, f);
-  for arg in args.iter() {
-    v.invocation_argument(arg);
-    invocation_argument(v, arg);
-  }
-}
-
-fn invocation_argument<V: ASTVisitor>(v: &mut V, arg: &InvocationArgument) {
-  use InvocationArgument::*;
-  match arg {
-    Positional(expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Keyword { expr, .. } => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Ignored => (),
-  }
-}
-
-fn index<V: ASTVisitor>(v: &mut V, indexee: &Expression, indexers: &Vec<Expression>) {
-  v.expression(indexee);
-  for i in indexers.iter() {
-    v.expression(i);
-  }
-}
-
-fn named_struct<V: ASTVisitor>(v: &mut V, n: &QualifiedName, fields: &Vec<(Rc<String>, Expression)>) {
-  v.qualified_name(n);
-  for (_, expr) in fields.iter() {
-    v.expression(expr);
-  }
-}
-
-fn lambda<V: ASTVisitor>(v: &mut V, params: &Vec<FormalParam>, type_anno: Option<&TypeIdentifier>, body: &Block) {
-  for param in params {
-    v.formal_param(param);
-    formal_param(v, param);
-  }
-  v.type_annotation(type_anno);
-  v.block(body);
-  walk_block(v, body);
-}
-
-fn formal_param<V: ASTVisitor>(v: &mut V, param: &FormalParam) {
-  param.default.as_ref().map(|p| {
-    v.expression(p);
-    expression(v, p);
-  });
-  v.type_annotation(param.anno.as_ref());
-}
-
-fn expression_kind<V: ASTVisitor>(v: &mut V, expression_kind: &ExpressionKind) {
-  use ExpressionKind::*;
-  match expression_kind {
-    NatLiteral(n) => v.nat_literal(*n),
-    FloatLiteral(f) => v.float_literal(*f),
-    StringLiteral(s) => v.string_literal(s),
-    BoolLiteral(b) => v.bool_literal(*b),
-    BinExp(op, lhs, rhs) => {
-      v.binexp(op, lhs, rhs);
-      expression(v, lhs);
-      expression(v, rhs);
-    },
-    PrefixExp(op, arg) => {
-      v.prefix_exp(op, arg);
-      expression(v, arg);
-    }
-    TupleLiteral(exprs) => {
-      for expr in exprs {
-        v.expression(expr);
-        expression(v, expr);
-      }
-    },
-    Value(name) => v.qualified_name(name),
-    NamedStruct { name, fields } => {
-      v.named_struct(name, fields);
-      named_struct(v, name, fields);
-    }
-    Call { f, arguments } => {
-      v.call(f, arguments);
-      call(v, f, arguments);
-    },
-    Index { indexee, indexers } => {
-      v.index(indexee, indexers);
-      index(v, indexee, indexers);
-    },
-    IfExpression { discriminator, body } => {
-      v.if_expression(deref_optional_box(discriminator), body);
-      discriminator.as_ref().map(|d| expression(v, d));
-      if_expression_body(v, body);
-    },
-    WhileExpression { condition, body } => v.while_expression(deref_optional_box(condition), body),
-    ForExpression { enumerators, body } => v.for_expression(enumerators, body),
-    Lambda { params , type_anno, body } => {
-      v.lambda(params, type_anno.as_ref(), body);
-      lambda(v, params, type_anno.as_ref(), body);
-    },
-    ListLiteral(exprs) => {
-      for expr in exprs {
-        v.expression(expr);
-        expression(v, expr);
-      }
-    },
-  }
-}
-
-fn if_expression_body<V: ASTVisitor>(v: &mut V, body: &IfExpressionBody) {
-  use IfExpressionBody::*;
-  match body {
-    SimpleConditional { then_case, else_case } => {
-      walk_block(v, then_case);
-      else_case.as_ref().map(|block| walk_block(v, block));
-    },
-    SimplePatternMatch { pattern, then_case, else_case } => {
-      v.pattern(pattern);
-      walk_pattern(v, pattern);
-      walk_block(v, then_case);
-      else_case.as_ref().map(|block| walk_block(v, block));
-    },
-    CondList(arms) => {
-      for arm in arms {
-        v.condition_arm(arm);
-        condition_arm(v, arm);
-      }
-    }
-  }
-}
-
-fn condition_arm<V: ASTVisitor>(v: &mut V, arm: &ConditionArm) {
-  use Condition::*;
-  v.condition_arm(arm);
-  match arm.condition {
-    Pattern(ref pat) => {
-      v.pattern(pat);
-      walk_pattern(v, pat);
-    },
-    TruncatedOp(ref _binop, ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    Expression(ref expr) => {
-      v.expression(expr);
-      expression(v, expr);
-    },
-    _ => ()
-  }
-  arm.guard.as_ref().map(|guard| {
-    v.expression(guard);
-    expression(v, guard);
-  });
-  v.block(&arm.body);
-  walk_block(v, &arm.body);
-}
-
-fn walk_pattern<V: ASTVisitor>(v: &mut V, pat: &Pattern) {
-  use Pattern::*;
-  match pat {
-    TuplePattern(patterns) => {
-      for pat in patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    TupleStruct(qualified_name, patterns) => {
-      v.qualified_name(qualified_name);
-      for pat in patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    Record(qualified_name, name_and_patterns) => {
-      v.qualified_name(qualified_name);
-      for (_, pat) in name_and_patterns {
-        v.pattern(pat);
-        walk_pattern(v, pat);
-      }
-    },
-    VarOrName(qualified_name) => {
-      v.qualified_name(qualified_name);
-    },
-    _ => ()
-  }
-}

schala-lang/language/src/builtin.rs

@@ -1,102 +1,145 @@
-use std::str::FromStr;
+use std::rc::Rc;
+use std::collections::HashMap;
+use std::fmt;
 
-use crate::typechecking::{TypeConst, Type};
+use crate::tokenizing::TokenKind;
+use self::BuiltinTypeSpecifier::*;
+use self::BuiltinTConst::*;
 
-#[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,
+
+#[derive(Debug, PartialEq, Clone)]
+pub enum BuiltinTypeSpecifier {
+  Const(BuiltinTConst),
+  Func(Box<BuiltinTypeSpecifier>, Box<BuiltinTypeSpecifier>),
 }
 
-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)
-    }
+#[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)
   }
 }
 
-impl FromStr for Builtin {
-  type Err = ();
+#[derive(Debug, PartialEq, Clone)]
+pub struct BinOp {
+  sigil: Rc<String>
+}
 
-  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(())
+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: &TokenKind) -> Option<BinOp> {
+    use self::TokenKind::*;
+    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: &TokenKind) -> Option<i32> {
+    use self::TokenKind::*;
+    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(|| {
+      default
+    }))
+  }
+
+  pub fn get_precedence(&self) -> i32 {
+    let s: &str = &self.sigil;
+    let default = 10_000_000;
+    BINOPS.get(s).map(|x| x.2.clone()).unwrap_or_else(|| {
+      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),
+      "quot" => (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(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/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

@@ -1,25 +1,33 @@
+
+use std::cell::RefCell;
 use std::rc::Rc;
 use std::fmt::Write;
 use std::io;
 
 use itertools::Itertools;
 
-use crate::schala::SymbolTableHandle;
 use crate::util::ScopeStack;
 use crate::reduced_ast::{BoundVars, ReducedAST, Stmt, Expr, Lit, Func, Alternative, Subpattern};
-use crate::symbol_table::{SymbolSpec, Symbol, SymbolTable, FullyQualifiedSymbolName};
-use crate::builtin::Builtin;
-
-mod test;
+use crate::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))))) });
+  }
 }
 
 impl<'a> State<'a> {
-  pub fn new() -> State<'a> {
-    let values = ScopeStack::new(Some(format!("global")));
-    State { values }
+  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 {
@@ -29,6 +37,7 @@ impl<'a> State<'a> {
   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() {
@@ -110,12 +119,16 @@ impl Expr {
         StringLit(s) => format!("\"{}\"", s),
       },
       Expr::Func(f) => match f {
-        BuiltIn(builtin) => format!("<built-in function '{:?}'>", builtin),
+        BuiltIn(name) => format!("<built-in function '{}'>", name),
         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::Constructor { 
+        type_name: _, name, 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),
@@ -127,8 +140,8 @@ impl Expr {
 
     match self {
       ConditionalTargetSigilValue => replacement.clone(),
-      Unit | Lit(_) | Func(_) | Sym(_) | Constructor { .. } |
-       CaseMatch { .. } | UnimplementedSigilValue | ReductionError(_) => self,
+      Unit | Lit(_) | Func(_) | Val(_) | Constructor { .. } |
+       CaseMatch { .. } | UnimplementedSigilValue => 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();
@@ -151,9 +164,7 @@ impl<'a> State<'a> {
 
     for statement in ast.0 {
       match self.statement(statement) {
-        Ok(Some(ref output)) if repl => {
-          acc.push(Ok(output.to_repl()))
-        },
+        Ok(Some(ref output)) if repl => acc.push(Ok(output.to_repl())),
         Ok(_) => (),
         Err(error) => {
           acc.push(Err(format!("Runtime error: {}", error)));
@@ -206,10 +217,7 @@ impl<'a> State<'a> {
       Node::Expr(expr) => match expr {
         literal @ Lit(_) => Ok(Node::Expr(literal)),
         Call { box f, args } => self.call_expression(f, args),
-        Sym(name) => Ok(match self.values.lookup(&name) {
-          Some(ValueEntry::Binding { val, .. }) => val.clone(),
-          None => return Err(format!("Could not look up symbol {}", name))
-        }),
+        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)),
@@ -223,7 +231,6 @@ impl<'a> State<'a> {
         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)),
       }
     }
   }
@@ -239,7 +246,7 @@ impl<'a> State<'a> {
 
   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));
+      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>,_>>()?;
@@ -253,7 +260,7 @@ impl<'a> State<'a> {
 
   fn apply_function(&mut self, f: Func, args: Vec<Expr>) -> EvalResult<Node> {
     match f {
-      Func::BuiltIn(builtin) => Ok(self.apply_builtin(builtin, args)?),
+      Func::BuiltIn(sigil) => Ok(Node::Expr(self.apply_builtin(sigil, args)?)),
       Func::UserDefined { params, body, name } => {
 
         if params.len() != args.len() {
@@ -261,6 +268,7 @@ impl<'a> State<'a> {
         }
         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))?;
@@ -272,84 +280,81 @@ impl<'a> State<'a> {
     }
   }
 
-  fn apply_builtin(&mut self, builtin: Builtin, args: Vec<Expr>) -> EvalResult<Node> {
+  fn apply_builtin(&mut self, name: Rc<String>, args: Vec<Expr>) -> EvalResult<Expr> {
     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: 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 (builtin, evaled_args.as_slice()) {
-      (FieldAccess, &[Node::PrimObject { .. }]) => {
-        //TODO implement field access
-        unimplemented!()
+    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))),
+      ("quot", &[Lit(Nat(l)), Lit(Nat(r))]) => if r == 0 {
+        return Err(format!("divide by zero"));
+      } else {
+        Lit(Nat(l / r))
       },
-      (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)),
+      ("%", &[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 */
-        (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)),
+      /* 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)),
 
-        (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)),
+      ("<", &[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)),
 
-        (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)),
+      ("<=", &[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)),
 
-        (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)),
+      (">", &[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)),
 
-        (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]) => {
+      ("print", &[ref anything]) => {
         print!("{}", anything.to_repl());
-        Expr::Unit.to_node()
+        Expr::Unit
       },
-      (IOPrintLn, &[ref anything]) => {
+      ("println", &[ref anything]) => {
         println!("{}", anything.to_repl());
-        Expr::Unit.to_node()
+        Expr::Unit
       },
-      (IOGetLine, &[]) => {
+      ("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()))).to_node()
+        Lit(StringLit(Rc::new(buf.trim().to_string())))
       },
       (x, args) => return Err(format!("bad or unimplemented builtin {:?} | {:?}", x, args)),
     })
@@ -366,7 +371,7 @@ impl<'a> State<'a> {
 
   fn assign_expression(&mut self, val: Expr, expr: Expr) -> EvalResult<Node> {
     let name = match val  {
-      Expr::Sym(name) => name,
+      Expr::Val(name) => name,
       _ => return Err(format!("Trying to assign to a non-value")),
     };
 
@@ -420,15 +425,15 @@ impl<'a> State<'a> {
     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)? {
+      if !self.guard_passes(&alt.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)? {
+          if alt.tag.map(|t| t == *tag).unwrap_or(true) {
+            let mut inner_state = self.new_frame(items, &alt.bound_vars);
+            if all_subpatterns_pass(&mut inner_state, &alt.subpatterns, items)? {
               return inner_state.block(alt.item);
             } else {
               continue;
@@ -436,15 +441,15 @@ impl<'a> State<'a> {
           }
         },
         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)? {
+          let mut inner_state = self.new_frame(items, &alt.bound_vars);
+          if all_subpatterns_pass(&mut inner_state, &alt.subpatterns, items)? {
             return inner_state.block(alt.item);
           } else {
             continue;
           }
         },
         Node::Expr(ref _e) => {
-          if let None = alt.matchable.tag {
+          if let None = alt.tag {
             return self.block(alt.item)
           }
         }
@@ -452,4 +457,292 @@ impl<'a> State<'a> {
     }
     Err(format!("{:?} failed pattern match", cond))
   }
+
+  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!(),
+        },
+        SymbolSpec::RecordConstructor { .. } => return Err(format!("This shouldn't be a record!")),
+      },
+      /* 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 crate::tokenizing::{Token, tokenize};
+  use crate::parsing::ParseResult;
+  use crate::ast::AST;
+  use crate::symbol_table::SymbolTable;
+  use crate::eval::State;
+
+  fn parse(tokens: Vec<Token>) -> ParseResult<AST> {
+    let mut parser = crate::parsing::Parser::new(tokens);
+    parser.parse()
+  }
+
+  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 ast = parse(tokenize(input)).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! 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 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 = Some(9); if x is Some(q) then { q } else { 0 }"#;
+    test_in_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 }"#;
+    test_in_fresh_env!(source, "0");
+  }
+
+  #[test]
+  fn full_if_matching() {
+    let source = r#"
+type Option<T> = Some(T) | None
+let a = None
+if a { is None -> 4, is Some(x) -> x }
+"#;
+  test_in_fresh_env!(source, "4");
+
+    let source = r#"
+type Option<T> = Some(T) | None
+let a = Some(99)
+if a { is None -> 4, is 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 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 = Mulch(20)
+let b = Jugs(1, "haha")
+let c = Mardok
+
+let x = if a {
+  is Mulch(20) -> "x",
+  is _ -> "ERR"
+}
+
+let y = if b {
+  is Mulch(n) -> "ERR",
+  is Jugs(2, _) -> "ERR",
+  is Jugs(1, s) -> s,
+  is _ -> "ERR",
+}
+
+let z = if c {
+  is Jugs(_, _) -> "ERR",
+  is 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/eval/test.rs

@@ -1,269 +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 (mut ast, source_map) = crate::util::quick_ast(input);
-  let source_map = Rc::new(RefCell::new(source_map));
-  let symbol_table = Rc::new(RefCell::new(SymbolTable::new(source_map)));
-  symbol_table.borrow_mut().add_top_level_symbols(&ast).unwrap();
-  {
-  let mut scope_resolver = ScopeResolver::new(symbol_table.clone());
-  let _ = scope_resolver.resolve(&mut ast);
-  }
-
-  let reduced = reduce(&ast, &symbol_table.borrow());
-  let mut state = State::new();
-  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 queque() {
-      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 then 4, is Option::Some(x) then 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 then 4, is Option::Some(x) then x }
-"#;
-test_in_fresh_env!(source, "99");
-
-let source = r#"
-let a = 10
-if a { is 10 then "x", is 4 then "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-
-let source = r#"
-let a = 10
-if a { is 15 then "x", is 10 then "y" }
-"#;
-test_in_fresh_env!(source, "\"y\"");
-}
-
-#[test]
-fn string_pattern() {
-  let source = r#"
-let a = "foo"
-if a { is "foo" then "x", is _ then "y" }
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern() {
-  let source = r#"
-let a = true
-if a {
-  is true then "x",
-  is false then "y"
-}
-"#;
-test_in_fresh_env!(source, "\"x\"");
-}
-
-#[test]
-fn boolean_pattern_2() {
-  let source = r#"
-let a = false
-if a { is true then "x", is false then "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 _ then "hella"
-}
-"#;
-test_in_fresh_env!(source, "\"hella\"");
-}
-
-#[test]
-fn tuple_pattern() {
-  let source = r#"
-if (1, 2) {
-  is (1, x) then x,
-  is _ then 99
-}
-"#;
-test_in_fresh_env!(source, 2);
-}
-
-
-#[test]
-fn tuple_pattern_2() {
-  let source = r#"
-if (1, 2) {
-  is (10, x) then x,
-  is (y, x) then x + y
-}
-"#;
-test_in_fresh_env!(source, 3);
-}
-
-#[test]
-fn tuple_pattern_3() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) then x,
-  is (1, x) then x
-}
-"#;
-test_in_fresh_env!(source, 5);
-}
-
-#[test]
-fn tuple_pattern_4() {
-  let source = r#"
-if (1, 5) {
-  is (10, x) then x,
-  is (1, x) then 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) then "x",
-  is _ then "ERR"
-}
-
-let y = if b {
-  is Stuff::Mulch(n) then "ERR",
-  is Stuff::Jugs(2, _) then "ERR",
-  is Stuff::Jugs(1, s) then s,
-  is _ then "ERR",
-}
-
-let z = if c {
-  is Stuff::Jugs(_, _) then "ERR",
-  is Stuff::Mardok then "NIGH",
-  is _ then "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");
-  }
-
-#[test]
-fn import_all() {
-  let source = r#"
-type Option<T> = Some(T) | None
-import Option::*
-let x = Some(9); if x is Some(q) then { q } else { 0 }"#;
-  test_in_fresh_env!(source, "9");
-}

schala-lang/language/src/lib.rs

@@ -1,4 +1,7 @@
-#![feature(box_patterns, box_syntax, trace_macros, or_patterns)]
+#![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
@@ -11,35 +14,200 @@ extern crate lazy_static;
 extern crate maplit;
 extern crate schala_repl;
 #[macro_use]
+extern crate schala_repl_codegen;
+#[macro_use]
 extern crate schala_lang_codegen;
-extern crate ena;
-extern crate derivative;
-extern crate colored;
-extern crate radix_trie;
 
+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) }
 }
 
-#[macro_use]
 mod util;
-#[macro_use]
-mod typechecking;
-mod debugging;
-
+mod builtin;
 mod tokenizing;
 mod ast;
-mod parser;
 mod parsing;
-#[macro_use]
 mod symbol_table;
-mod scope_resolution;
-mod builtin;
+mod typechecking;
 mod reduced_ast;
 mod eval;
-mod source_map;
 
-mod schala;
+//trace_macros!(true);
+#[derive(ProgrammingLanguageInterface)]
+#[LanguageName = "Schala"]
+#[SourceFileExtension = "schala"]
+#[PipelineSteps(load_source, tokenizing, parsing(compact,expanded,trace), symbol_table, typechecking, ast_reducing, eval)]
+#[DocMethod = get_doc]
+#[HandleCustomInterpreterDirectives = handle_custom_interpreter_directives]
+/// All bits of 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>,
+}
 
-pub use schala::Schala;
+impl Schala {
+  fn get_doc(&self, commands: &Vec<&str>) -> Option<String> {
+    Some(format!("Documentation on commands: {:?}", commands))
+  }
+
+  fn handle_custom_interpreter_directives(&mut self, commands: &Vec<&str>) -> Option<String> {
+    Some(format!("Schala-lang command: {:?} not supported", commands.get(0)))
+  }
+}
+
+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();
+    s.execute_pipeline(prelude, &EvalOptions::default());
+    s
+  }
+}
+
+fn load_source<'a>(input: &'a str, handle: &mut Schala, _comp: Option<&mut UnfinishedComputation>) -> Result<&'a str, String> {
+  handle.source_reference.load_new_source(input);
+  Ok(input)
+}
+
+fn tokenizing(input: &str, _handle: &mut Schala, comp: Option<&mut UnfinishedComputation>) -> 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(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(input: Vec<tokenizing::Token>, handle: &mut Schala, comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+  use crate::parsing::Parser;
+
+  let mut parser = match handle.active_parser.take() {
+    None => Parser::new(input),
+    Some(parser) => parser
+  };
+
+  let ast = parser.parse();
+  let trace = parser.format_parse_trace();
+
+  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| 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 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(input: ast::AST, handle: &mut Schala, comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+  let result = handle.type_context.typecheck(&input);
+
+  comp.map(|comp| {
+    let artifact = TraceArtifact::new("type", format!("{:?}", result));
+    comp.add_artifact(artifact);
+  });
+
+  Ok(input)
+}
+
+fn ast_reducing(input: ast::AST, handle: &mut Schala, 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(input: reduced_ast::ReducedAST, handle: &mut Schala, 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
+}
+
+/// 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"))
+  }
+}

schala-lang/language/src/parser.rs

@@ -1,598 +0,0 @@
-extern crate nom;
-
-use std::rc::Rc;
-use std::str::FromStr;
-
-use nom::IResult;
-use nom::character::complete::{one_of, space0, alphanumeric0};
-use nom::bytes::complete::{tag, take, take_while, take_while1, take_until};
-use nom::combinator::{cut, cond, map, map_res, value, opt, verify};
-use nom::multi::{separated_list, separated_nonempty_list, many1, many0};
-use nom::error::{context, ParseError, VerboseError, ErrorKind, make_error};
-use nom::branch::alt;
-use nom::sequence::{pair, tuple, delimited, preceded};
-
-use crate::ast::*;
-use crate::builtin::Builtin;
-
-type ParseResult<'a, T> = IResult<&'a str, T, VerboseError<&'a str>>;
-
-pub fn ws<'a, O, E: ParseError<&'a str>, F>(parser: F) -> impl Fn(&'a str) -> IResult<&'a str, O, E>
-where
-    F: Fn(&'a str) -> IResult<&'a str, O, E>,
-    {
-      delimited(space0, parser, space0)
-    }
-
-fn statement_sep(text: &str) -> ParseResult<()> {
-  value((), one_of("\n;"))(text)
-}
-
-fn single_alphabetic_character(text: &str) -> ParseResult<char> {
-  let p = verify(take(1usize), |s: &str| s.chars().nth(0).map(|c| c.is_alphabetic()).unwrap_or(false));
-  map(p, |s: &str| s.chars().nth(0).unwrap())(text)
-}
-
-fn single_alphanumeric_character(text: &str) -> ParseResult<char> {
-  let p = verify(take(1usize), |s: &str| s.chars().nth(0).map(|c| c.is_alphanumeric() || c == '_').unwrap_or(false));
-  map(p, |s: &str| s.chars().nth(0).unwrap())(text)
-}
-
-fn identifier(text: &str) -> ParseResult<Rc<String>> {
-  use nom::character::complete::char;
-  map(alt((
-    pair(char('_'), many1(single_alphanumeric_character)),
-    pair(single_alphabetic_character, many0(single_alphanumeric_character))
-  )),
-  |(first, rest): (char, Vec<char>)| Rc::new(format!("{}{}", first, rest.into_iter().collect::<String>()))
-  )(text)
-}
-
-const OPERATOR_CHARS: &'static str = "~`!@#$%^&*-+=<>?/|";
-fn operator(text: &str) -> ParseResult<Vec<char>> {
-  many1(one_of(OPERATOR_CHARS))(text)
-}
-
-fn binop(text: &str) -> ParseResult<BinOp> {
-  context("Binop", map(
-      operator,
-      |op| BinOp::from_sigil(&op.into_iter().collect::<String>())
-  ))(text)
-}
-
-fn bool_literal(text: &str) -> ParseResult<ExpressionKind> {
-  let p = alt((
-    value(true, tag("true")),
-    value(false, tag("false"))
-  ));
-  context("Bool literal", map(p, ExpressionKind::BoolLiteral))(text)
-}
-
-fn number_literal(text: &str) -> ParseResult<ExpressionKind> {
-  let num_lit = many1(alt((
-    map(one_of("1234567890"), |s: char| Some(s)),
-    value(None, nom::character::complete::char('_')),
-  )));
-
-  let (text, n) = map_res(num_lit,
-    |digits: Vec<Option<char>>| {
-      let num_str: String = digits.into_iter().filter_map(|x| x).collect();
-      u64::from_str_radix(&num_str, 10)
-    })(text)?;
-
-  Ok((text, ExpressionKind::NatLiteral(n)))
-}
-
-fn binary_literal(text: &str) -> ParseResult<ExpressionKind> {
-  let p = preceded(tag("0b"), cut(take_while1(|c: char| c == '0' || c == '1')));
-  let (rest, n): (&str, u64) = map_res(
-    p, |hex_str: &str| u64::from_str_radix(hex_str, 2)
-  )(text)?;
-  let expr = ExpressionKind::NatLiteral(n);
-  Ok((rest, expr))
-}
-
-fn hex_literal(text: &str) -> ParseResult<ExpressionKind> {
-  let p = preceded(tag("0x"), cut(take_while1(|c: char| c.is_digit(16))));
-  let (rest, n): (&str, u64) = map_res(
-    p, |hex_str: &str| u64::from_str_radix(hex_str, 16)
-  )(text)?;
-  let expr = ExpressionKind::NatLiteral(n);
-  Ok((rest, expr))
-}
-
-fn string_literal(text: &str) -> ParseResult<ExpressionKind> {
-  use nom::character::complete::char;
-  let (text, string_output) = delimited(
-    char('"'), take_until("\""), char('"')
-  )(text)?;
-  let expr = ExpressionKind::StringLiteral(Rc::new(string_output.to_string()));
-  Ok((text, expr))
-}
-
-fn literal(text: &str) -> ParseResult<ExpressionKind> {
-  alt((
-    string_literal,
-    hex_literal,
-    binary_literal,
-    number_literal,
-    bool_literal,
-  ))(text)
-}
-
-fn paren_expr(text: &str) -> ParseResult<ExpressionKind> {
-  context("Paren expression", delimited(tag("("), ws(expression_kind), tag(")")))(text)
-}
-
-fn prefix_op(text: &str) -> ParseResult<PrefixOp> {
-  use nom::character::complete::char;
-  let p = alt((char('+'), char('-'), char('!')));
-  map(p, |sigil| PrefixOp::from_str(&sigil.to_string()).unwrap())(text)
-}
-
-fn qualified_name(text: &str) -> ParseResult<QualifiedName> {
-  map(
-    separated_nonempty_list(tag("::"), identifier),
-    |components| QualifiedName { id: ItemId::new(0), components }
-  )(text)
-}
-
-fn identifier_expr(text: &str) -> ParseResult<ExpressionKind> {
-  map(qualified_name, ExpressionKind::Value)(text)
-}
-
-fn primary_expr(text: &str) -> ParseResult<ExpressionKind> {
-  // primary := literal | paren_expr | if_expr | for_expr | while_expr | identifier_expr | lambda_expr | anonymous_struct | list_expr
-
-  alt((
-    if_expr,
-    for_expr,
-    while_expr,
-    literal,
-    paren_expr,
-    lambda_expr,
-    identifier_expr,
-  ))(text)
-}
-
-fn lambda_expr(text: &str) -> ParseResult<ExpressionKind> {
-  let p = preceded(ws(tag("\\")),
-    tuple((ws(lambda_param_list), ws(opt(type_anno)), ws(block))));
-  context("Lambda expression",
-    map(p, |(params, type_anno, body)| ExpressionKind::Lambda { params, type_anno, body })
-  )(text)
-}
-
-fn lambda_param_list(text: &str) -> ParseResult<Vec<FormalParam>> {
-  alt((
-    map(formal_param, |x| vec![x]),
-    formal_params
-  ))(text)
-}
-
-
-fn while_expr(text: &str) -> ParseResult<ExpressionKind> {
-  let p = preceded(tag("while"), tuple((ws(while_cond), ws(block))));
-  let m = map(p, |(condition, body)| {
-    let condition = condition.map(Box::new);
-    ExpressionKind::WhileExpression {condition, body}
-  });
-  context("While expression", m)(text)
-}
-
-fn while_cond(text: &str) -> ParseResult<Option<Expression>> {
-  //TODO support is constructs?
-  context("While condition",
-   map(opt(ws(expression_kind)),
-   |maybe_expr_kind| maybe_expr_kind.map(|kind| Expression::new(ItemId::new(0), kind)))
-  )(text)
-}
-
-fn for_expr(text: &str) -> ParseResult<ExpressionKind> {
-  //TODO do I need something like no struct literal here?
-  let en = alt((
-    map(enumerator, |e| vec![e]),
-    delimited(tag("{"), enumerators, tag("}"))
-  ));
-  context("For expression",
-  preceded(tag("for"),
-  cut(
-    map(tuple((ws(en), for_expr_body)),
-    |(enumerators, body)| ExpressionKind::ForExpression { enumerators, body: Box::new(body) }
-  ))))(text)
-}
-
-
-fn enumerators(text: &str) -> ParseResult<Vec<Enumerator>> {
-  separated_nonempty_list(alt((value((), tag(",")), statement_sep)),
-    enumerator)(text)
-}
-
-fn enumerator(text: &str) -> ParseResult<Enumerator> {
-  map(
-    tuple((ws(identifier), ws(tag("<-")), ws(expression))),
-  |(id, _, generator)| Enumerator { id, generator }
-  )(text)
-}
-
-fn for_expr_body(text: &str) -> ParseResult<ForBody> {
-  context("For expression body",
-  alt((
-    map(preceded(ws(tag("return")), expression), ForBody::MonadicReturn),
-    map(block, ForBody::StatementBlock),
-  )))(text)
-}
-
-fn invocation_argument(text: &str) -> ParseResult<InvocationArgument> {
-  use nom::character::complete::char;
-  alt((
-    value(InvocationArgument::Ignored, pair(char('_'), alphanumeric0)),
-    map(expression_kind, |kind: ExpressionKind| InvocationArgument::Positional(
-        Expression {  id: ItemId::new(0), kind, type_anno: None }))
-    //map(identifier, |id: Rc<String>| 
-  ))(text)
-}
-
-fn if_expr(text: &str) -> ParseResult<ExpressionKind> {
-  let p = preceded(tag("if"), pair(ws(discriminator), ws(if_expr_body)));
-  map(p, |(discriminator, body)| {
-    let discriminator = discriminator.map(Box::new);
-    let body = Box::new(body);
-    ExpressionKind::IfExpression { discriminator, body }
-  }) (text)
-}
-
-fn discriminator(text: &str) -> ParseResult<Option<Expression>> {
-  use nom::combinator::verify;
-  cond(text.chars().next().map(|c| c != '{').unwrap_or(true),
-    expression
-  )(text)
-}
-
-fn if_expr_body(text: &str) -> ParseResult<IfExpressionBody> {
-  alt((
-    preceded(tag("then"), simple_conditional),
-    preceded(tag("is"), simple_pattern_match),
-    cond_block,
-  ))(text)
-}
-
-fn simple_conditional(text: &str) -> ParseResult<IfExpressionBody> {
-  map(
-    pair(expr_or_block, else_case),
-    |(then_case, else_case)| IfExpressionBody::SimpleConditional { then_case, else_case }
-  )(text)
-}
-
-fn else_case(text: &str) -> ParseResult<Option<Block>> {
-  opt(preceded(tag("else"), expr_or_block))(text)
-}
-
-fn simple_pattern_match(text: &str) -> ParseResult<IfExpressionBody> {
-  let p = tuple((pattern, tag("then"), expr_or_block, else_case));
-  map(p, |(pattern, _, then_case, else_case)| 
-    IfExpressionBody::SimplePatternMatch { pattern, then_case, else_case }
-  )(text)
-}
-
-fn pattern(text: &str) -> ParseResult<Pattern> {
-  use nom::character::complete::char;
-
-  let t = delimited(char('('), 
-    separated_nonempty_list(char(','), pattern),
-    char(')')
-  );
-
-  alt((
-    map(t, |patterns| Pattern::TuplePattern(patterns)),
-    simple_pattern,
-  ))(text)
-}
-
-fn simple_pattern(text: &str) -> ParseResult<Pattern> {
-  alt((
-    value(Pattern::Ignored, tag("_")),
-    tuple_struct_pattern,
-    record_pattern,
-    map(pattern_literal, Pattern::Literal),
-    map(qualified_name, Pattern::VarOrName),
-  ))(text)
-}
-
-fn tuple_struct_pattern(text: &str) -> ParseResult<Pattern> {
-  let p = tuple((
-    qualified_name, 
-    delimited(ws(tag("(")),
-    separated_nonempty_list(ws(tag(",")), ws(pattern)),
-    ws(tag(")"))
-    )
-  ));
-  map(p, |(name, patterns)| Pattern::TupleStruct(name, patterns))(text)
-}
-
-fn record_pattern(text: &str) -> ParseResult<Pattern> {
-  let p = tuple((
-    qualified_name,
-    delimited(ws(tag("{")),
-    separated_nonempty_list(ws(tag(",")), ws(record_pattern_entry)), //TODO support newlines?
-    ws(tag("}")))
-  ));
-  map(p, |(name, members)| Pattern::Record(name, members))(text)
-}
-
-fn record_pattern_entry(text: &str) -> ParseResult<(Rc<String>, Pattern)> {
-  alt((
-    map(tuple((ws(identifier), ws(tag(":")), ws(pattern))),
-      |(name, _, pattern)| (name, pattern)),
-    map(identifier, |name|
-      (name.clone(), Pattern::Literal(PatternLiteral::StringPattern(name.clone())))
-    )
-  ))(text)
-}
-
-fn pattern_literal(text: &str) -> ParseResult<PatternLiteral> {
-  use PatternLiteral::*;
-  use nom::character::complete::char;
-  alt((
-    value(BoolPattern(true), tag("true")),
-    value(BoolPattern(false), tag("false")),
-    map(delimited(char('"'), take_until("\""), char('"')), |s: &str| StringPattern(Rc::new(s.to_string()))),
-  ))(text)
-    //TODO handle signed_number_literal
-}
-
-fn cond_block(text: &str) -> ParseResult<IfExpressionBody> {
-  use nom::character::complete::char;
-  //TODO maybe change this bit of syntax
-  let comma_or_delimitor = alt((value((), char(',')), statement_sep));
-  let p = delimited(char('{'),
-    separated_nonempty_list(comma_or_delimitor, cond_arm),
-  char('}'));
-  map(p, IfExpressionBody::CondList)(text)
-}
-
-fn cond_arm(text: &str) -> ParseResult<ConditionArm> {
-  let variant_1 = map(
-    tuple((condition, guard, tag("then"), expr_or_block)),
-    |(condition, guard, _, body)| ConditionArm { condition, guard, body }
-  );
-  let variant_2 = map(
-    preceded(tag("else"), expr_or_block),
-    |body| ConditionArm { condition: Condition::Else, guard: None, body }
-  );
-  alt((variant_1, variant_2))(text)
-}
-
-fn condition(text: &str) -> ParseResult<Condition> {
-  alt((
-    map(preceded(tag("is"), pattern), Condition::Pattern),
-    map(tuple((binop, expression)), |(op, expr)|
-      Condition::TruncatedOp(op, expr)),
-    map(expression, Condition::Expression),
-  ))(text)
-}
-
-fn guard(text: &str) -> ParseResult<Option<Expression>> {
-  opt(preceded(tag("if"), expression))(text)
-}
-
-fn expr_or_block(text: &str) -> ParseResult<Block> {
-  //TODO fix
-  alt((block, map(expression, |expr| vec![Statement { id: ItemId::new(0), kind: StatementKind::Expression(expr)}])))(text)
-}
-
-fn block(text: &str) -> ParseResult<Block> {
-  //TODO fix this so it can handle nested statements
-  let make_expr = |e| Statement { id: ItemId::new(0), kind: StatementKind::Expression(e) };
-  delimited(ws(tag("{")),
-    delimited(opt(many0(statement_sep)),
-      separated_list(many1(statement_sep),
-        map(expression, make_expr)
-      ),
-      opt(many0(statement_sep))
-    ),
-  ws(tag("}")))(text)
-}
-
-fn call_expr(text: &str) -> ParseResult<ExpressionKind> {
-  use nom::character::complete::char;
-  let parse_call = opt(
-    delimited(char('('), separated_list(char(','), invocation_argument), char(')'))
-  );
-  let p = pair(primary_expr, parse_call);
-  map(p, |(expr, call_part)| if let Some(arguments) = call_part {
-    let f = bx!(Expression { id: ItemId::new(0), kind: expr, type_anno: None }); 
-    ExpressionKind::Call { f, arguments }
-  } else {
-    expr
-  })(text)
-}
-
-fn prefix_expr(text: &str) -> ParseResult<ExpressionKind> {
-  let (text, pfx) = ws(opt(prefix_op))(text)?;
-  let (text, result) = call_expr(text)?;
-  match pfx {
-    None => Ok((text, result)),
-    Some(pfx) => {
-      let exp = Expression { id: ItemId::new(0), kind: result, type_anno: None }; 
-      Ok((text, ExpressionKind::PrefixExp(pfx, Box::new(exp))))
-    }
-  }
-}
-
-// this implements Pratt parsing, see http://journal.stuffwithstuff.com/2011/03/19/pratt-parsers-expression-parsing-made-easy/
-fn precedence_expr(text: &str) -> ParseResult<ExpressionKind> {
-  fn inner_precedence_expr(input: &str, precedence: i32) -> ParseResult<ExpressionKind> {
-    let (mut outer_rest, mut lhs) = prefix_expr(input)?;
-    loop {
-      let (rest, _) = space0(outer_rest)?;
-      let (rest, maybe_binop) = opt(binop)(rest)?;
-      let (new_precedence, binop) = match maybe_binop {
-        Some(binop) => (binop.precedence(), binop),
-        None => break,
-      };
-
-      if precedence >= new_precedence {
-        break;
-      }
-      let (rest, _) = space0(rest)?;
-      let (rest, rhs) = inner_precedence_expr(rest, new_precedence)?;
-      outer_rest = rest;
-      lhs = ExpressionKind::BinExp(binop,
-        bx!(Expression::new(ItemId::new(0), lhs)),
-        bx!(Expression::new(ItemId::new(0), rhs))
-      );
-    }
-    Ok((outer_rest, lhs))
-  }
-  context("Precedence expression",
-    |input| inner_precedence_expr(input, BinOp::min_precedence())
-  )(text)
-}
-
-fn expression_kind(text: &str) -> ParseResult<ExpressionKind> {
-  context("Expression kind", ws(precedence_expr))(text)
-}
-
-fn type_anno(text: &str) -> ParseResult<TypeIdentifier> {
-  preceded(ws(tag(":")), ws(type_name))(text)
-}
-
-fn type_name(text: &str) -> ParseResult<TypeIdentifier> {
-  //TODO incomplete
-  let (text, name) = identifier(text)?;
-  let id = TypeIdentifier::Singleton(TypeSingletonName { name, params: vec![] });
-  Ok((text, id))
-}
-
-pub fn expression(text: &str) -> ParseResult<Expression> {
-  let (rest, (kind, type_anno)) = ws(pair(expression_kind, opt(type_anno)))(text)?;
-  let expr = Expression { id: ItemId::new(0), kind, type_anno };
-  Ok((rest, expr))
-}
-
-fn import(text: &str) -> ParseResult<ImportSpecifier> {
-  let p = preceded(
-    tag("import"),
-    separated_nonempty_list(tag("::"), identifier)
-  );
-  map(p, |path_components| ImportSpecifier {
-    id: ItemId::new(0),
-    path_components,
-    imported_names: ImportedNames::LastOfPath, //TODO finish
-  })(text)
-}
-
-fn module(text: &str) -> ParseResult<ModuleSpecifier> {
-  let p = tuple((tag("module"), ws(identifier), ws(block)));
-  map(p, |(_, name, contents)| ModuleSpecifier { name, contents })
-    (text)
-}
-
-fn declaration(text: &str) -> ParseResult<Declaration> {
-  alt((
-    func_declaration,
-    type_declaration,
-  ))(text)
-}
-
-fn func_declaration(text: &str) -> ParseResult<Declaration> {
-  use Declaration::*;
-  let p = tuple((func_signature, ws(opt(block))));
-  map(p, |(signature, maybe_block)| match maybe_block {
-    Some(block) => FuncDecl(signature, block),
-    None => FuncSig(signature),
-  })(text)
-}
-
-fn func_signature(text: &str) -> ParseResult<Signature> {
-  let p = preceded(tag("fn"), cut(tuple((ws(identifier), ws(formal_params), opt(ws(type_anno))))));
-  //TODO fix op
-  map(p, |(name, params, type_anno)| Signature { name, params, type_anno, operator: false })
-    (text)
-}
-
-fn formal_params(text: &str) -> ParseResult<Vec<FormalParam>> {
-  delimited(tag("("), ws(separated_list(ws(tag(",")), formal_param)), tag(")"))(text)
-}
-
-fn formal_param(text: &str) -> ParseResult<FormalParam> {
-  let default = opt(preceded(ws(tag("=")), ws(expression)));
-  let p = tuple((ws(identifier), opt(ws(type_anno)), default));
-  map(p, |(name, anno, default)|
-    FormalParam { name, anno, default })(text)
-}
-
-fn type_declaration(text: &str) -> ParseResult<Declaration> {
-  preceded(tag("type"), ws(type_declaration_body))(text)
-}
-
-fn type_declaration_body(text: &str) -> ParseResult<Declaration> {
-  let t = tuple((opt(tag("mut")), ws(type_singleton_name), ws(tag("=")), ws(type_body)));
-  alt((
-    preceded(tag("alias"), ws(type_alias)),
-    map(t, |(mut_kw, name, _, body)| {
-      Declaration::TypeDecl { name, body, mutable: mut_kw.is_some() }
-    })
-  ))(text)
-}
-
-fn type_body(text: &str) -> ParseResult<TypeBody> {
-  let p = separated_nonempty_list(ws(tag("|")), variant_specifier);
-  map(p, TypeBody)(text)
-}
-
-fn variant_specifier(text: &str) -> ParseResult<Variant> {
-  use self::Variant::*;
-  let tuple_struct =
-    delimited(tag("("), separated_nonempty_list(ws(tag(",")), type_name), ws(tag(")")));
-  //TODO record
-
-  let p = tuple((identifier, opt(tuple_struct)));
-  map(p, |(name, maybe_tuple_members)| match maybe_tuple_members {
-    Some(members) => TupleStruct(name, members),
-    None => UnitStruct(name),
-  })(text)
-}
-
-fn type_singleton_name(text: &str) -> ParseResult<TypeSingletonName> {
-  let p = tuple((identifier, opt(delimited(tag("<"),
-    separated_nonempty_list(tag(","), ws(type_name)),
-  tag(">")))));
-  map(p, |(name, params)| TypeSingletonName { name, params: params.unwrap_or(vec![]) })(text)
-}
-
-fn type_alias(text: &str) -> ParseResult<Declaration> {
-  let p = tuple((ws(identifier), ws(tag("=")), ws(identifier)));
-  map(p, |(alias, _, original)| Declaration::TypeAlias { alias, original })
-    (text)
-}
-
-fn statement(text: &str) -> ParseResult<Statement> {
-  let p = alt((
-    map(import, StatementKind::Import),
-    map(module, StatementKind::Module),
-    map(declaration, StatementKind::Declaration),
-    map(expression, StatementKind::Expression),
-  ));
-  map(p, |kind| Statement { id: ItemId::new(0), kind })(text)
-}
-
-pub fn parse_ast(text: &str) -> ParseResult<AST> {
-  map(separated_list(statement_sep, statement),
-  |statements| AST { id: ItemId::new(0), statements }
-  )(text)
-}
-
-pub fn perform_parsing(input: &str) -> Result<String, String> {
-  let output = match parse_ast(input) {
-    Ok((rest, ast)) => format!("{:?} (rest: {})", ast, rest),
-    Err(nom::Err::Incomplete(needed)) => format!("Incomplete: {:?}" ,needed),
-    Err(nom::Err::Error(verbose_error) | nom::Err::Failure(verbose_error)) => {
-      format!("Verbose Error: ` {:?} `", verbose_error)
-      //nom::error::convert_error(input, verbose_error)
-    }
-  };
-      
-  Ok(output)
-}

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

@@ -1,849 +0,0 @@
-#![cfg(test)]
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::str::FromStr;
-
-use super::{Parser, ParseResult, tokenize, ParseError};
-use crate::ast::*;
-use super::Declaration::*;
-use super::Signature;
-use super::TypeIdentifier::*;
-use super::TypeSingletonName;
-use super::ExpressionKind::*;
-use super::Variant::*;
-use super::ForBody::*;
-
-/*
-fn make_parser(input: &str) -> Parser {
-  let source_map = crate::source_map::SourceMap::new();
-  let source_map_handle = Rc::new(RefCell::new(source_map));
-  let tokens: Vec<crate::tokenizing::Token> = tokenize(input);
-  let mut parser = super::Parser::new(source_map_handle);
-  parser.add_new_tokens(tokens);
-  parser
-}
-*/
-
-fn parse(input: &str) -> ParseResult<AST> {
-  use crate::tokenizing::*;
-  crate::parser::parse_ast(input).map_err(|err| {
-    let token = Token { kind: TokenKind::Newline, location: crate::source_map::Location { line_num: 0, char_num: 0 } };
-    ParseError { production_name: None, msg: "".to_string(), token  }
-  })
-  .map(|(rest, s)| s)
-  /*
-  let mut parser = make_parser(input);
-  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! import {
-  ($import_spec:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Import($import_spec) }
-  }
-}
-
-macro_rules! module {
-  ($module_spec:expr) => {
-    Statement { id: ItemIdStore::new_id(), kind: StatementKind::Module($module_spec) }
-  }
-}
-
-macro_rules! ex {
-  ($expr_type:expr) => { Expression::new(ItemIdStore::new_id(), $expr_type) };
-  ($expr_type:expr, $type_anno:expr) => { Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno) };
-  (s $expr_text:expr) => {
-    {
-      /*
-      let mut parser = make_parser($expr_text);
-      parser.expression().unwrap()
-      */
-      crate::parser::expression($expr_text).unwrap().1
-    }
-  };
-}
-
-macro_rules! inv {
-  ($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) => { Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::new(ItemIdStore::new_id(), $expr_type).into())} };
-  ($expr_type:expr, $type_anno:expr) => { Statement { id: ItemIdStore::new_id(), kind: StatementKind::Expression(Expression::with_anno(ItemIdStore::new_id(), $expr_type, $type_anno).into())} };
-  ($op:expr, $lhs:expr, $rhs:expr) => { Statement { id: ItemIdStore::new_id(), ,kind: StatementKind::Expression(ex!(binexp!($op, $lhs, $rhs)))}
-  };
-  (s $statement_text:expr) => {
-    {
-      /*
-      let mut parser = make_parser($statement_text);
-      parser.statement().unwrap()
-      */
-      Statement {
-        kind: StatementKind::Expression(
-        crate::parser::expression($statement_text).unwrap().1
-        ),
-        id: ItemIdStore::new_id()
-    }
-    }
-  }
-}
-
-#[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!(val!("a"))), indexers: vec![ex!(val!("b")), ex!(val!("c"))]} ));
-
-  parse_test_wrap_ast!("None", exst!(val!("None")));
-  parse_test_wrap_ast!("Pandas {  a: x + y }",
-    exst!(NamedStruct { name: qname!(Pandas), fields: vec![(rc!(a), ex!(binexp!("+", val!("x"), val!("y"))))]})
-  );
-  parse_test_wrap_ast! { "Pandas { a: n, b: q, }",
-    exst!(NamedStruct { name: qname!(Pandas), fields:
-    vec![(rc!(a), ex!(val!("n"))), (rc!(b), ex!(val!("q")))]
-    }
-    )
-  };
-}
-
-
-#[test]
-fn qualified_identifiers() {
-  parse_test_wrap_ast! {
-    "let q_q = Yolo::Swaggins",
-    decl!(Binding { name: rc!(q_q), constant: true, type_anno: None,
-    expr: Expression::new(ItemIdStore::new_id(), Value(qname!(Yolo, Swaggins))),
-    })
-  }
-
-  parse_test_wrap_ast! {
-    "thing::item::call()",
-    exst!(Call { f: bx![ex!(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()",  decl!(FuncSig(Signature { name: rc!(oi), operator: false, params: vec![], type_anno: None })));
-  parse_test_wrap_ast!("oi()", exst!(Call { f: bx!(ex!(val!("oi"))), arguments: vec![] }));
-  parse_test_wrap_ast!("oi(a, 2 + 2)", exst!(Call
-  { f: bx!(ex!(val!("oi"))),
-    arguments: vec![inv!(ex!(val!("a"))), inv!(ex!(binexp!("+", NatLiteral(2), NatLiteral(2)))).into()]
-  }));
-  parse_error!("a(b,,c)");
-
-  parse_test_wrap_ast!("fn a(b, c: Int): Int", 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() }", 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!(val!("x"))), arguments: vec![] })])));
-  parse_test_wrap_ast!("fn a(x) {\n x() }", 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!(val!("x"))), arguments: vec![] })])));
-
-  let multiline = r#"
-fn a(x) {
-x()
-}
-"#;
-parse_test_wrap_ast!(multiline, 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!(val!("x"))), arguments: vec![] })])));
-  let multiline2 = r#"
-fn a(x) {
-
-x()
-
-}
-"#;
-parse_test_wrap_ast!(multiline2, 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) { }",
-    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(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", decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: false} ));
-  parse_test_wrap_ast!("type mut Yolo = Yolo", decl!(TypeDecl { name: tys!("Yolo"), body: TypeBody(vec![UnitStruct(rc!(Yolo))]), mutable: true} ));
-  parse_test_wrap_ast!("type alias Sex = Drugs", decl!(TypeAlias { alias: rc!(Sex), original: rc!(Drugs) }));
-  parse_test_wrap_ast!("type Sanchez = Miguel | Alejandro(Int, Option<a>) | Esperanza { a: Int, b: String }",
-  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)",
-    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", decl!(Binding { name: rc!(a), constant: false, type_anno: None, expr: ex!(NatLiteral(10)) } ));
-  parse_test_wrap_ast!("let a = 2 + 2", decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr: ex!(binexp!("+", NatLiteral(2), NatLiteral(2))) }));
-  parse_test_wrap_ast!("let a: Nat = 2 + 2", decl!(
-      Binding { name: rc!(a), constant: true, type_anno: Some(Singleton(TypeSingletonName { name: rc!(Nat), params: vec![] })),
-      expr: ex!(binexp!("+", NatLiteral(2), NatLiteral(2))) }
-  ));
-}
-
-#[test]
-fn parsing_block_expressions() {
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() }", exst!(
-      IfExpression {
-        discriminator: Some(bx! {
-          ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})
-        }),
-        body: bx! {
-          IfExpressionBody::SimpleConditional {
-            then_case: vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-            else_case: None,
-          }
-        }
-      }
-    )
-  };
-
-  parse_test_wrap_ast! {
-    "if a() then { b(); c() } else { q }", exst!(
-      IfExpression {
-        discriminator: Some(bx! {
-          ex!(Call { f: bx!(ex!(val!("a"))), arguments: vec![]})
-        }),
-        body: bx! {
-          IfExpressionBody::SimpleConditional {
-            then_case: vec![exst!(Call { f: bx!(ex!(val!("b"))), arguments: vec![]}), exst!(Call { f: bx!(ex!(val!("c"))), arguments: vec![] })],
-            else_case: 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 }",
-  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(); }",
-  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(); }",
-  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) { }",
-  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() }",
-  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",
-    decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr:
-      ex!(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!(
-      Lambda {
-        params: vec![
-          FormalParam { name: rc!(x), anno: None, default: None }
-        ],
-        type_anno: None,
-        body: vec![exst!(s "y")] }
-      )),
-      arguments: vec![inv!(ex!(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!(Call { f: bx!(ex!(val!("wahoo"))), arguments: vec![] })),
-          arguments: vec![inv!(ex!(NatLiteral(3))).into()],
-        }
-      }
-    ]
-  }
-  }
-}
-
-#[test]
-  fn list_literals() {
-    parse_test_wrap_ast! {
-      "[1,2]",
-        exst!(ListLiteral(vec![ex!(NatLiteral(1)), ex!(NatLiteral(2))]))
-    };
-  }
-
-#[test]
-fn while_expr() {
-  parse_test_wrap_ast! {
-    "while { 3 }",
-    exst!(WhileExpression { condition: None, body: vec![ exst!(s "3")] })
-  }
-
-  parse_test_wrap_ast! {
-    "while a == b { 3 }",
-    exst!(WhileExpression { condition: Some(bx![ex![binexp!("==", val!("a"), val!("b"))]]), body: vec![ exst!(s "3")] })
-  }
-}
-
-#[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: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::TupleStruct(qname!(Some), vec![Pattern::VarOrName(qname!(a))]),
-          then_case: vec![exst!(s "4")],
-          else_case: Some(vec![exst!(s "9")]) })
-        }
-      )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Some(a) then 4 else 9", exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-            pattern: Pattern::TupleStruct(qname!(Some), vec![Pattern::VarOrName(qname!(a))]),
-            then_case: vec![exst!(s "4")],
-            else_case: Some(vec![exst!(s "9")]) }
-          )
-        }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is Something { a, b: x } then { 4 } else { 9 }", exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::Record(qname!(Something), vec![
-                (rc!(a),Pattern::Literal(PatternLiteral::StringPattern(rc!(a)))),
-                (rc!(b),Pattern::VarOrName(qname!(x)))
-            ]),
-          then_case: vec![exst!(s "4")],
-          else_case: Some(vec![exst!(s "9")])
-          }
-        )
-      }
-    )
-  }
-}
-
-#[test]
-fn pattern_literals() {
-  parse_test_wrap_ast! {
-    "if x is -1 then 1 else 2",
-    exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-            pattern: Pattern::Literal(PatternLiteral::NumPattern { neg: true, num: NatLiteral(1) }),
-            then_case: vec![exst!(NatLiteral(1))],
-            else_case: Some(vec![exst!(NatLiteral(2))]),
-        })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is 1 then 1 else 2",
-    exst!(
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::SimplePatternMatch {
-          pattern: Pattern::Literal(PatternLiteral::NumPattern { neg: false, num: NatLiteral(1) }),
-          then_case: vec![exst!(s "1")],
-          else_case: Some(vec![exst!(s "2")]),
-        })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is true then 1 else 2",
-    exst!(
-    IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(
-            IfExpressionBody::SimplePatternMatch {
-              pattern: Pattern::Literal(PatternLiteral::BoolPattern(true)),
-              then_case: vec![exst!(NatLiteral(1))],
-              else_case: Some(vec![exst!(NatLiteral(2))]),
-          })
-      }
-    )
-  }
-
-  parse_test_wrap_ast! {
-    "if x is \"gnosticism\" then 1 else 2",
-      exst!(
-        IfExpression {
-          discriminator: Some(bx!(ex!(s "x"))),
-          body: bx!(IfExpressionBody::SimplePatternMatch {
-              pattern: Pattern::Literal(PatternLiteral::StringPattern(rc!(gnosticism))),
-              then_case: vec![exst!(s "1")],
-              else_case: Some(vec![exst!(s "2")]),
-          })
-        }
-      )
-  }
-}
-
-#[test]
-fn imports() {
-  parse_test_wrap_ast! {
-    "import harbinger::draughts::Norgleheim",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(harbinger), rc!(draughts), rc!(Norgleheim)],
-      imported_names: ImportedNames::LastOfPath
-    })
-  }
-}
-
-#[test]
-fn imports_2() {
-  parse_test_wrap_ast! {
-    "import harbinger::draughts::{Norgleheim, Xraksenlaigar}",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(harbinger), rc!(draughts)],
-      imported_names: ImportedNames::List(vec![
-        rc!(Norgleheim),
-        rc!(Xraksenlaigar)
-      ])
-    })
-  }
-}
-
-#[test]
-fn imports_3() {
-  parse_test_wrap_ast! {
-    "import bespouri::{}",
-    import!(ImportSpecifier { 
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(bespouri)],
-      imported_names: ImportedNames::List(vec![])
-    })
-  }
-}
-
-
-#[test]
-fn imports_4() {
-  parse_test_wrap_ast! {
-    "import bespouri::*",
-    import!(ImportSpecifier {
-      id: ItemIdStore::new_id(),
-      path_components: vec![rc!(bespouri)],
-      imported_names: ImportedNames::All
-    })
-  }
-}
-
-
-#[test]
-fn if_expr() {
-  parse_test_wrap_ast! {
-    "if x { is 1 then 5, else 20 }",
-    exst! {
-      IfExpression {
-        discriminator: Some(bx!(ex!(s "x"))),
-        body: bx!(IfExpressionBody::CondList(
-          vec![
-            ConditionArm {
-              condition: Condition::Pattern(Pattern::Literal(PatternLiteral::NumPattern { neg: false, num: NatLiteral(1)})),
-              guard: None,
-              body: vec![exst!(s "5")],
-            },
-            ConditionArm {
-              condition: Condition::Else,
-              guard: None,
-              body: vec![exst!(s "20")],
-            },
-          ]
-        ))
-      }
-    }
-  }
-}
-
-#[test]
-fn modules() {
-  parse_test_wrap_ast! {
-r#"
-  module ephraim {
-    let a = 10
-    fn nah() { 33 }
-  }
-"#,
-module!(
-  ModuleSpecifier { name: rc!(ephraim), contents: vec![
-    decl!(Binding { name: rc!(a), constant: true, type_anno: None, expr: ex!(s "10") }),
-    decl!(FuncDecl(Signature { name: rc!(nah), operator: false, params: vec![], type_anno: None }, vec![exst!(NatLiteral(33))])),
-  ] }
-)
-  }
-}

schala-lang/language/src/prelude.schala

@@ -1,14 +1,13 @@
-let _SCHALA_VERSION = "0.1.0"
 
 type Option<T> = Some(T) | None
+type Color = Red | Green | Blue
 type Ord = LT | EQ | GT
 
 
 fn map(input: Option<T>, func: Func): Option<T> {
   if input {
-    is Option::Some(x) then Option::Some(func(x)),
-    is Option::None then Option::None,
+    is Some(x) -> Some(func(x)),
+    is None -> None,
   }
 }
-
-type Complicated = Sunrise | Metal { black: bool, norwegian: bool } | Fella(String, Int)
+  

schala-lang/language/src/reduced_ast.rs

@@ -1,24 +1,8 @@
-//! # 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;
-use crate::util::deref_optional_box;
+use crate::symbol_table::{Symbol, SymbolSpec, SymbolTable};
+use crate::builtin::{BinOp, PrefixOp};
 
 #[derive(Debug)]
 pub struct ReducedAST(pub Vec<Stmt>);
@@ -42,21 +26,21 @@ pub enum Stmt {
 pub enum Expr {
   Unit,
   Lit(Lit),
-  Sym(Rc<String>), //a Sym is anything that can be looked up by name at runtime - i.e. a function or variable address
   Tuple(Vec<Expr>),
   Func(Func),
+  Val(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
+    arity: usize,
   },
   Call {
     f: Box<Expr>,
     args: Vec<Expr>,
   },
   Assign {
-    val: Box<Expr>, //TODO this probably can't be a val
+    val: Box<Expr>,
     expr: Box<Expr>,
   },
   Conditional {
@@ -69,15 +53,17 @@ pub enum Expr {
     cond: Box<Expr>,
     alternatives: Vec<Alternative>
   },
-  UnimplementedSigilValue,
-  ReductionError(String),
+  UnimplementedSigilValue
 }
 
 pub type BoundVars = Vec<Option<Rc<String>>>; //remember that order matters here
 
 #[derive(Debug, Clone)]
 pub struct Alternative {
-  pub matchable: Subpattern,
+  pub tag: Option<usize>,
+  pub subpatterns: Vec<Option<Subpattern>>,
+  pub guard: Option<Expr>,
+  pub bound_vars: BoundVars,
   pub item: Vec<Stmt>,
 }
 
@@ -100,7 +86,7 @@ pub enum Lit {
 
 #[derive(Debug, Clone)]
 pub enum Func {
-  BuiltIn(Builtin),
+  BuiltIn(Rc<String>),
   UserDefined {
     name: Option<Rc<String>>,
     params: Vec<Rc<String>>,
@@ -108,272 +94,129 @@ pub enum Func {
   }
 }
 
-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 {
+impl AST {
+  pub fn reduce(&self, symbol_table: &SymbolTable) -> ReducedAST {
     let mut output = vec![];
-    for statement in ast.statements.iter() {
-      output.push(self.statement(statement));
+    for statement in self.0.iter() {
+      output.push(statement.node().reduce(symbol_table));
     }
     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),
-      StatementKind::Import(_) => Stmt::Noop,
-      StatementKind::Module(modspec) => {
-        for statement in modspec.contents.iter() {
-          self.statement(&statement);
-        }
-        Stmt::Noop
-      }
+impl Statement {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Stmt { 
+    use crate::ast::Statement::*;
+    match self {
+      ExpressionStatement(expr) => Stmt::Expr(expr.node().reduce(symbol_table)),
+      Declaration(decl) => decl.reduce(symbol_table),
     }
   }
+}
 
-  fn block(&mut self, block: &Block) -> Vec<Stmt> {
-    block.iter().map(|stmt| self.statement(stmt)).collect()
-  }
+fn reduce_block(block: &Block, symbol_table: &SymbolTable) -> Vec<Stmt> {
+  block.iter().map(|stmt| stmt.node().reduce(symbol_table)).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;
+impl Expression {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Expr {
+    use crate::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) => self.binop(binop, lhs, rhs),
-      PrefixExp(op, arg) => self.prefix(op, arg),
-      Value(qualified_name) => self.value(qualified_name),
-      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(deref_optional_box(discriminator), body),
-      Lambda { params, body, .. } => self.reduce_lambda(params, body),
-      NamedStruct { name, fields } => self.reduce_named_struct(name, fields),
+      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.node().reduce(symbol_table)).collect(),
+      },
+      TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| e.node().reduce(symbol_table)).collect()),
+      IfExpression { discriminator, body } => reduce_if_expression(discriminator, body, symbol_table),
+      Lambda { params, body, .. } => reduce_lambda(params, body, symbol_table),
+      NamedStruct { .. } => Expr::UnimplementedSigilValue,
       Index { .. } => Expr::UnimplementedSigilValue,
       WhileExpression { .. } => Expr::UnimplementedSigilValue,
       ForExpression { .. } => Expr::UnimplementedSigilValue,
       ListLiteral { .. } => Expr::UnimplementedSigilValue,
     }
   }
+}
 
-  fn value(&mut self, qualified_name: &QualifiedName) -> Expr {
-    let symbol_table = self.symbol_table;
-    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)),
-    };
+fn reduce_lambda(params: &Vec<FormalParam>, body: &Block, symbol_table: &SymbolTable) -> Expr {
+  Expr::Func(Func::UserDefined {
+    name: None,
+    params: params.iter().map(|param| param.0.clone()).collect(),
+    body: reduce_block(body, symbol_table),
+  })
+}
 
-    //TODO this probably needs to change
-    let FullyQualifiedSymbolName(ref v) = sym_name;
-    let name = v.last().unwrap().name.clone();
+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!("Can't yet handle binop discriminators")
+  });
+  match *body {
+    IfExpressionBody::SimpleConditional(ref then_clause, ref else_clause) => {
+      let then_clause = reduce_block(then_clause, symbol_table);
+      let else_clause = match else_clause {
+        None => vec![],
+        Some(stmts) => reduce_block(stmts, symbol_table),
+      };
+      Expr::Conditional { cond, then_clause, else_clause }
+    },
+    IfExpressionBody::SimplePatternMatch(ref pat, ref then_clause, ref else_clause) => {
+      let then_clause = reduce_block(then_clause, symbol_table);
+      let else_clause = match else_clause {
+        None => vec![],
+        Some(stmts) => reduce_block(stmts, symbol_table),
+      };
 
-    let Symbol { local_name, spec, .. } = match symbol_table.lookup_by_fqsn(&sym_name) {
-      Some(s) => s,
-      //None => return Expr::ReductionError(format!("Symbol {:?} not found", sym_name)),
-      None => return Expr::Sym(name.clone())
-    };
+      let alternatives = vec![
+        pat.to_alternative(then_clause, symbol_table),
+        Alternative {
+          tag: None,
+          subpatterns: vec![],
+          bound_vars: vec![],
+          guard: None,
+          item: else_clause
+        },
+      ];
 
-    match spec {
-      SymbolSpec::RecordConstructor { .. } => Expr::ReductionError(format!("AST reducer doesn't expect a RecordConstructor here")),
-      SymbolSpec::DataConstructor { index, type_args, type_name } => Expr::Constructor {
-        type_name: type_name.clone(),
-        name: name.clone(),
-        tag: index.clone(),
-        arity: type_args.len(),
-      },
-      SymbolSpec::Func(_) => Expr::Sym(local_name.clone()),
-      SymbolSpec::Binding => Expr::Sym(local_name.clone()), //TODO not sure if this is right, probably needs to eventually be fqsn
-      SymbolSpec::Type { .. } => Expr::ReductionError("AST reducer doesnt expect a type here".to_string())
-    }
-  }
-
-  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: Option<&Expression>, body: &IfExpressionBody) -> Expr {
-    let symbol_table = self.symbol_table;
-    let cond = Box::new(match discriminator {
-      Some(expr) => self.expression(expr),
-      None => return Expr::ReductionError(format!("blank cond if-expr not supported")),
-    });
-
-    match body {
-      IfExpressionBody::SimpleConditional { then_case, else_case } => {
-        let then_clause = self.block(&then_case);
-        let else_clause = match else_case.as_ref() {
-          None => vec![],
-          Some(stmts) => self.block(&stmts),
-        };
-        Expr::Conditional { cond, then_clause, else_clause }
-      },
-      IfExpressionBody::SimplePatternMatch { pattern, then_case, else_case } => {
-        let then_clause = self.block(&then_case);
-        let else_clause = match else_case.as_ref() {
-          None => vec![],
-          Some(stmts) => self.block(&stmts),
-        };
-
-        let alternatives = vec![
-          pattern.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 = reduce_block(&arm.body, symbol_table);
+            let alt = p.to_alternative(item, symbol_table);
+            alternatives.push(alt);
           },
-        ];
-
-        Expr::CaseMatch {
-          cond,
-          alternatives,
-        }
-      },
-      IfExpressionBody::CondList(ref condition_arms) => {
-        let mut alternatives = vec![];
-        for arm in condition_arms {
-          match arm.condition {
-            Condition::Expression(ref _expr) => {
-              return Expr::UnimplementedSigilValue
-            },
-            Condition::Pattern(ref p) =>  {
-              let item = self.block(&arm.body);
-              let alt = p.to_alternative(item, symbol_table);
-              alternatives.push(alt);
-            },
-            Condition::TruncatedOp(_, _) => {
-              return Expr::UnimplementedSigilValue
-            },
-            Condition::Else => {
-              return Expr::UnimplementedSigilValue
-            }
+          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)
+      Expr::CaseMatch { cond, alternatives }
     }
   }
 }
-
-
-
-
-
 /*                     ig var   pat
  * x is SomeBigOldEnum(_, x, Some(t))
  */
@@ -385,26 +228,13 @@ fn handle_symbol(symbol: Option<&Symbol>, inner_patterns: &Vec<Pattern>, symbol_
     _ => 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");
-        }
-      }
-    },
+    Literal(PatternLiteral::VarPattern(var)) => Some(var.clone()),
     _ => None,
   }).collect();
 
   let subpatterns = inner_patterns.iter().map(|p| match p {
     Ignored => None,
-    VarOrName(_) => None,
+    Literal(PatternLiteral::VarPattern(_)) => 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)),
@@ -433,12 +263,10 @@ 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,
-      },
+      tag: s.tag,
+      subpatterns: s.subpatterns,
+      bound_vars: s.bound_vars,
+      guard: s.guard,
       item
     }
   }
@@ -446,14 +274,9 @@ impl Pattern {
   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);
-          }
-        }
+      TupleStruct(name, inner_patterns) => {
+        let symbol = symbol_table.lookup_by_name(name).expect(&format!("Symbol {} not found", name));
+        handle_symbol(Some(symbol), inner_patterns, symbol_table)
       },
       TuplePattern(inner_patterns) => handle_symbol(None, inner_patterns, symbol_table),
       Record(_name, _pairs) => {
@@ -461,45 +284,24 @@ impl Pattern {
       },
       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.
-        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 {
+  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),
+          (false, ExpressionType::NatLiteral(n)) => Lit::Nat(*n),
+          (false, ExpressionType::FloatLiteral(f)) => Lit::Float(*f),
+          (true, ExpressionType::NatLiteral(n)) => Lit::Int(-1*(*n as i64)),
+          (true, ExpressionType::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))),
+          f: Box::new(Expr::Func(Func::BuiltIn(Rc::new("==".to_string())))),
           args: vec![comparison, Expr::ConditionalTargetSigilValue],
         });
         Subpattern {
@@ -511,7 +313,7 @@ impl PatternLiteral {
       },
       StringPattern(s) => {
         let guard = Some(Expr::Call {
-          f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
+          f: Box::new(Expr::Func(Func::BuiltIn(Rc::new("==".to_string())))),
           args: vec![Expr::Lit(Lit::StringLit(s.clone())), Expr::ConditionalTargetSigilValue]
         });
 
@@ -527,7 +329,7 @@ impl PatternLiteral {
           Expr::ConditionalTargetSigilValue
         } else {
           Expr::Call {
-            f: Box::new(Expr::Func(Func::BuiltIn(Builtin::BooleanNot))),
+            f: Box::new(Expr::Func(Func::BuiltIn(Rc::new("!".to_string())))),
             args: vec![Expr::ConditionalTargetSigilValue]
           }
         });
@@ -538,7 +340,59 @@ impl PatternLiteral {
           bound_vars: vec![],
         }
       },
+      VarPattern(var) => match symbol_table.lookup_by_name(var) {
+        Some(symbol) => handle_symbol(Some(symbol), &vec![], symbol_table),
+        None => Subpattern {
+          tag: None,
+          subpatterns: vec![],
+          guard: None,
+          bound_vars: vec![Some(var.clone())],
+        }
+      }
     }
   }
-
+}
+
+impl Declaration {
+  fn reduce(&self, symbol_table: &SymbolTable) -> Stmt {
+    use self::Declaration::*;
+    use crate::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: reduce_block(&statements, symbol_table),
+        }
+      },
+      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<Node<Expression>>, rhs: &Box<Node<Expression>>) -> Expr {
+    if **self.sigil() == "=" {
+      Expr::Assign {
+        val: Box::new(lhs.node().reduce(symbol_table)),
+        expr: Box::new(rhs.node().reduce(symbol_table)),
+      }
+    } else {
+      let f = Box::new(Expr::Func(Func::BuiltIn(self.sigil().clone())));
+      Expr::Call { f, args: vec![lhs.node().reduce(symbol_table), rhs.node().reduce(symbol_table)]}
+    }
+  }
+}
+
+impl PrefixOp {
+  fn reduce(&self, symbol_table: &SymbolTable, arg: &Box<Node<Expression>>) -> Expr {
+    let f = Box::new(Expr::Func(Func::BuiltIn(self.sigil().clone())));
+    Expr::Call { f, args: vec![arg.node().reduce(symbol_table)]}
+  }
 }

schala-lang/language/src/schala.rs

@@ -1,340 +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, parser, eval, typechecking, symbol_table, source_map};
-
-pub type SymbolTableHandle = Rc<RefCell<symbol_table::SymbolTable>>;
-pub type SourceMapHandle = Rc<RefCell<source_map::SourceMap>>;
-
-/// 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,
-  source_map: SourceMapHandle,
-  state: eval::State<'static>,
-  symbol_table: SymbolTableHandle,
-  resolver: crate::scope_resolution::ScopeResolver<'static>,
-  type_context: typechecking::TypeContext<'static>,
-  active_parser: 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 source_map = Rc::new(RefCell::new(source_map::SourceMap::new()));
-    let symbols = Rc::new(RefCell::new(symbol_table::SymbolTable::new(source_map.clone())));
-    Schala {
-      //TODO maybe these can be the same structure
-      source_reference: SourceReference::new(),
-      symbol_table: symbols.clone(),
-      source_map: source_map.clone(),
-      resolver: crate::scope_resolution::ScopeResolver::new(symbols.clone()),
-      state: eval::State::new(),
-      type_context: typechecking::TypeContext::new(),
-      active_parser: parsing::Parser::new(source_map)
-    }
-  }
-
-  /// 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() };
-    let response = s.run_computation(request);
-    if let Err(msg) = response.main_output {
-      panic!("Error in prelude, panicking: {}", msg);
-    }
-    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 ParsingDebugType::*;
-
-  let ref mut parser = handle.active_parser;
-  parser.add_new_tokens(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.source_reference))
-}
-
-fn format_parse_error(error: parsing::ParseError, source_reference: &SourceReference) -> String {
-  let line_num = error.token.location.line_num;
-  let ch = error.token.location.char_num;
-  let line_from_program = 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);
-
-  let production = match error.production_name {
-    Some(n) => format!("\n(from production \"{}\")", n),
-    None => "".to_string()
-  };
-
-  format!(r#"
-{error_msg}{production}
-{space_padding} |
-{line_num} | {}
-{space_padding} | {}
-"#, line_from_program, location_pointer, error_msg=error.msg, space_padding=space_padding, line_num=line_num, production=production
-)
-}
-
-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 () = handle.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
-    };
-
-    let main_output = parser::perform_parsing(source);
-
-    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

@@ -1,119 +0,0 @@
-use std::rc::Rc;
-
-use crate::schala::SymbolTableHandle;
-use crate::symbol_table::{ScopeSegment, FullyQualifiedSymbolName};
-use crate::ast::*;
-use crate::util::ScopeStack;
-
-type FQSNPrefix = Vec<ScopeSegment>;
-
-pub struct ScopeResolver<'a> {
-  symbol_table_handle: SymbolTableHandle,
-  name_scope_stack: ScopeStack<'a, Rc<String>, FQSNPrefix>,
-}
-
-impl<'a> ASTVisitor for ScopeResolver<'a> {
-  //TODO need to un-insert these - maybe need to rethink visitor
-  fn import(&mut self, import_spec: &ImportSpecifier) {
-    let ref symbol_table = self.symbol_table_handle.borrow();
-    let ImportSpecifier { ref path_components, ref imported_names, .. } = &import_spec;
-    match imported_names {
-      ImportedNames::All => {
-        let prefix = FullyQualifiedSymbolName(path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect());
-        let members = symbol_table.lookup_children_of_fqsn(&prefix);
-        for member in members.into_iter() {
-          let local_name = member.0.last().unwrap().name.clone();
-          self.name_scope_stack.insert(local_name.clone(), member.0);
-        }
-      },
-      ImportedNames::LastOfPath => {
-        let name = path_components.last().unwrap(); //TODO handle better
-        let fqsn_prefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect();
-        self.name_scope_stack.insert(name.clone(), fqsn_prefix);
-      }
-      ImportedNames::List(ref names) => {
-        let fqsn_prefix: FQSNPrefix = path_components.iter().map(|c| ScopeSegment {
-          name: c.clone(),
-        }).collect();
-        for name in names.iter() {
-          self.name_scope_stack.insert(name.clone(), fqsn_prefix.clone());
-        }
-      }
-    };
-  }
-
-  fn qualified_name(&mut self, qualified_name: &QualifiedName) {
-    let ref mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let fqsn = self.lookup_name_in_scope(&qualified_name);
-    let ref id = qualified_name.id;
-    symbol_table.map_id_to_fqsn(id, fqsn);
-  }
-
-  fn named_struct(&mut self, name: &QualifiedName, _fields: &Vec<(Rc<String>, Expression)>) {
-    let ref mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let ref id = name.id;
-    let fqsn = self.lookup_name_in_scope(&name);
-    symbol_table.map_id_to_fqsn(id, fqsn);
-  }
-
-  fn pattern(&mut self, pat: &Pattern) {
-    use Pattern::*;
-    match pat {
-      Ignored => (),
-      TuplePattern(_) => (),
-      Literal(_) => (),
-      TupleStruct(name, _) => self.qualified_name_in_pattern(name),
-      Record(name, _) => self.qualified_name_in_pattern(name),
-      VarOrName(name) => self.qualified_name_in_pattern(name),
-    };
-  }
-}
-
-impl<'a> ScopeResolver<'a> {
-  pub fn new(symbol_table_handle: SymbolTableHandle) -> ScopeResolver<'static> {
-    let name_scope_stack = ScopeStack::new(None);
-    ScopeResolver { symbol_table_handle, name_scope_stack }
-  }
-  pub fn resolve(&mut self, ast: &mut AST) -> Result<(), String> {
-    walk_ast(self, ast);
-    Ok(())
-  }
-
-  fn lookup_name_in_scope(&self, sym_name: &QualifiedName) -> FullyQualifiedSymbolName {
-    let QualifiedName { components, .. } = sym_name;
-    let first_component = &components[0];
-    match self.name_scope_stack.lookup(first_component) {
-      None => {
-        FullyQualifiedSymbolName(components.iter().map(|name| ScopeSegment { name: name.clone() }).collect())
-      },
-      Some(fqsn_prefix) => {
-        let mut full_name = fqsn_prefix.clone();
-        let rest_of_name: FQSNPrefix = components[1..].iter().map(|name| ScopeSegment { name: name.clone() }).collect();
-        full_name.extend_from_slice(&rest_of_name);
-        FullyQualifiedSymbolName(full_name)
-      }
-    }
-  }
-
-  /// 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 mut symbol_table = self.symbol_table_handle.borrow_mut();
-    let ref id = qualified_name.id;
-    let fqsn = self.lookup_name_in_scope(qualified_name);
-    if symbol_table.lookup_by_fqsn(&fqsn).is_some() {
-      symbol_table.map_id_to_fqsn(&id, fqsn);
-    }
-  }
-}
-
-#[cfg(test)]
-mod tests {
-  #[test]
-  fn basic_scope() {
-
-  }
-}

schala-lang/language/src/source_map.rs

@@ -1,39 +0,0 @@
-use std::collections::HashMap;
-use std::fmt;
-
-use crate::ast::ItemId;
-
-pub type LineNumber = usize;
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub struct Location {
-  pub line_num: LineNumber,
-  pub char_num: usize,
-}
-
-impl fmt::Display for Location {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    write!(f, "{}:{}", self.line_num, self.char_num)
-  }
-}
-
-pub struct SourceMap {
-  map: HashMap<ItemId, Location>
-}
-
-impl SourceMap {
-  pub fn new() -> SourceMap {
-    SourceMap { map: HashMap::new() }
-  }
-
-  pub fn add_location(&mut self, id: &ItemId, loc: Location) {
-    self.map.insert(id.clone(), loc);
-  }
-
-  pub fn lookup(&self, id: &ItemId) -> Option<Location> {
-    match self.map.get(id) {
-      Some(loc) => Some(loc.clone()),
-      None => None
-    }
-  }
-}

schala-lang/language/src/symbol_table.rs

@@ -1,149 +1,38 @@
 use std::collections::HashMap;
-use std::collections::hash_map::Entry;
 use std::rc::Rc;
 use std::fmt;
 use std::fmt::Write;
 
-use crate::schala::SourceMapHandle;
-use crate::source_map::{SourceMap, LineNumber};
 use crate::ast;
-use crate::ast::{ItemId, TypeBody, TypeSingletonName, Signature, Statement, StatementKind, ModuleSpecifier};
+use crate::ast::{TypeBody, TypeSingletonName, Signature};
 use crate::typechecking::TypeName;
 
-
-#[allow(unused_macros)]
-macro_rules! fqsn {
-  ( $( $name:expr ; $kind:tt),* ) => {
-    {
-      let mut vec = vec![];
-      $(
-        vec.push(crate::symbol_table::ScopeSegment::new(std::rc::Rc::new($name.to_string())));
-      )*
-      FullyQualifiedSymbolName(vec)
-    }
-  };
-}
-
-mod symbol_trie;
-use symbol_trie::SymbolTrie;
-mod test;
-
-/// Keeps track of what names were used in a given namespace. Call try_register to add a name to
-/// the table, or report an error if a name already exists.
-struct DuplicateNameTrackTable {
-  table: HashMap<Rc<String>, LineNumber>,
-}
-
-impl DuplicateNameTrackTable {
-  fn new() -> DuplicateNameTrackTable {
-    DuplicateNameTrackTable { table: HashMap::new() }
-  }
-
-  fn try_register(&mut self, name: &Rc<String>, id: &ItemId, source_map: &SourceMap) -> Result<(), LineNumber> {
-    match self.table.entry(name.clone()) {
-      Entry::Occupied(o) => {
-        let line_number = o.get();
-        Err(*line_number)
-      },
-      Entry::Vacant(v) => {
-        let line_number = if let Some(loc) = source_map.lookup(id) {
-          loc.line_num
-        } else {
-          0
-        };
-        v.insert(line_number);
-        Ok(())
-      }
-    }
-  }
-}
-
-#[derive(PartialEq, Eq, Hash, Debug, Clone, PartialOrd, Ord)]
-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, PartialOrd, Ord)]
-pub struct ScopeSegment {
-  pub name: Rc<String>, //TODO maybe this could be a &str, for efficiency?
-}
-
-impl fmt::Display for ScopeSegment {
-  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    let kind = ""; //TODO implement some kind of kind-tracking here
-    write!(f, "{}{}", self.name, kind)
-  }
-}
-
-impl ScopeSegment {
-  pub fn new(name: Rc<String>) ->  ScopeSegment {
-    ScopeSegment { name }
-  }
-}
-
-
 //cf. p. 150 or so of Language Implementation Patterns
 pub struct SymbolTable {
-  source_map_handle: SourceMapHandle,
-  symbol_path_to_symbol: HashMap<FullyQualifiedSymbolName, Symbol>,
-  id_to_fqsn: HashMap<ItemId, FullyQualifiedSymbolName>,
-  symbol_trie: SymbolTrie,
+  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(source_map_handle: SourceMapHandle) -> SymbolTable {
-    SymbolTable {
-      source_map_handle,
-      symbol_path_to_symbol: HashMap::new(),
-      id_to_fqsn: HashMap::new(),
-      symbol_trie: SymbolTrie::new()
-    }
+  pub fn new() -> SymbolTable {
+    SymbolTable { values: 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, local_name: &Rc<String>, scope_path: &Vec<ScopeSegment>, spec: SymbolSpec) {
-    let mut vec: Vec<ScopeSegment> = scope_path.clone();
-    vec.push(ScopeSegment { name: local_name.clone() });
-    let fully_qualified_name = FullyQualifiedSymbolName(vec);
-    let symbol = Symbol { local_name: local_name.clone(), fully_qualified_name: fully_qualified_name.clone(), spec };
-    self.symbol_trie.insert(&fully_qualified_name);
-    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)
-  }
-
-  pub fn lookup_children_of_fqsn(&self, path: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
-    self.symbol_trie.get_children(path)
+  pub fn lookup_by_name(&self, name: &Rc<String>) -> Option<&Symbol> {
+    self.values.get(name)
   }
 }
 
 #[derive(Debug)]
 pub struct Symbol {
-  pub local_name: Rc<String>, //TODO does this need to be pub?
-  fully_qualified_name: FullyQualifiedSymbolName,
+  pub name: Rc<String>,
   pub spec: SymbolSpec,
 }
 
 impl fmt::Display for Symbol {
   fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    write!(f, "<Local name: {}, Spec: {}>", self.local_name, self.spec)
+    write!(f, "<Name: {}, Spec: {}>", self.name, self.spec)
   }
 }
 
@@ -152,18 +41,12 @@ pub enum SymbolSpec {
   Func(Vec<TypeName>),
   DataConstructor {
     index: usize,
-    type_name: TypeName,
+    type_name: Rc<String>,
     type_args: Vec<Rc<String>>,
   },
   RecordConstructor {
-    index: usize,
-    members: HashMap<Rc<String>, TypeName>,
-    type_name: TypeName,
-  },
-  Binding,
-  Type {
-    name: TypeName
-  },
+    fields: HashMap<Rc<String>, Rc<String>>
+  }
 }
 
 impl fmt::Display for SymbolSpec {
@@ -172,9 +55,7 @@ impl fmt::Display for 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"),
-      Type { name } => write!(f, "Type <{}>", name),
+      RecordConstructor { fields } => write!(f, "RecordConstructor( <fields> )"),
     }
   }
 }
@@ -182,146 +63,81 @@ impl fmt::Display for SymbolSpec {
 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::Statement;
     use self::ast::Declaration::*;
-
-    let mut seen_identifiers = DuplicateNameTrackTable::new();
-    let mut seen_modules = DuplicateNameTrackTable::new();
-
-    for statement in statements.iter() {
-      match statement {
-        Statement { kind: StatementKind::Declaration(decl), id } => {
-          match decl {
-            FuncSig(ref signature) => {
-              seen_identifiers.try_register(&signature.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate function definition: {}. It's already defined at {}", signature.name, line))?;
-              self.add_function_signature(signature, scope_name_stack)?
-            }
-            FuncDecl(ref signature, ref body) => {
-              seen_identifiers.try_register(&signature.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate function definition: {}. It's already defined at {}", signature.name, line))?;
-              self.add_function_signature(signature, scope_name_stack)?;
-              scope_name_stack.push(ScopeSegment{
-                name: signature.name.clone(),
-              });
-              let output = self.add_symbols_from_scope(body, scope_name_stack);
-              scope_name_stack.pop();
-              output?
-            },
-            TypeDecl { name, body, mutable } => {
-              seen_identifiers.try_register(&name.name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate type definition: {}. It's already defined at {}", name.name, line))?;
-              self.add_type_decl(name, body, mutable, scope_name_stack)?
-            },
-            Binding { name, .. } => {
-              seen_identifiers.try_register(&name, &id, &self.source_map_handle.borrow())
-                .map_err(|line| format!("Duplicate variable definition: {}. It's already defined at {}", name, line))?;
-              self.add_new_symbol(name, scope_name_stack, SymbolSpec::Binding);
-            }
-            _ => ()
-          }
-        },
-        Statement { kind: StatementKind::Module(ModuleSpecifier { name, contents}), id } => {
-          seen_modules.try_register(&name, &id, &self.source_map_handle.borrow())
-            .map_err(|line| format!("Duplicate module definition: {}. It's already defined at {}", name, line))?;
-          scope_name_stack.push(ScopeSegment { name: name.clone() });
-          let output = self.add_symbols_from_scope(contents, scope_name_stack);
-          scope_name_stack.pop();
-          output?
-        },
-        _ => ()
+    for statement in ast.0.iter() {
+      let statement = statement.node();
+      if let Statement::Declaration(decl) = statement {
+        match decl {
+          FuncSig(signature) | FuncDecl(signature, _) => self.add_function_signature(signature)?,
+          TypeDecl { name, body, mutable } => self.add_type_decl(name, body, mutable)?,
+          _ => ()
+        }
       }
     }
     Ok(())
   }
   pub fn debug_symbol_table(&self) -> String {
     let mut output = format!("Symbol table\n");
-    let mut sorted_symbols: Vec<(&FullyQualifiedSymbolName, &Symbol)> = self.symbol_path_to_symbol.iter().collect();
-    sorted_symbols.sort_by(|(fqsn, _), (other_fqsn, _)| fqsn.cmp(other_fqsn));
-    for (name, sym) in sorted_symbols.iter() {
+    for (name, sym) in &self.values {
       write!(output, "{} -> {}\n", name, sym).unwrap();
     }
     output
   }
 
-  fn add_function_signature(&mut self, signature: &Signature, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
+  fn add_function_signature(&mut self, signature: &Signature) -> 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()
+    let types = signature.params.iter().map(|param| match param {
+      (_, Some(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));
+    let spec = SymbolSpec::Func(types);
+    self.values.insert(
+      signature.name.clone(),
+      Symbol { name: signature.name.clone(), spec }
+    );
     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> {
+  fn add_type_decl(&mut self, type_name: &TypeSingletonName, body: &TypeBody, _mutable: &bool) -> Result<(), String> {
     use crate::ast::{TypeIdentifier, Variant};
     let TypeBody(variants) = body;
-    let ref type_name = type_name.name;
-
-
-    let type_spec = SymbolSpec::Type {
-      name: type_name.clone(),
-    };
-    self.add_new_symbol(type_name, &scope_name_stack, type_spec);
-
-    scope_name_stack.push(ScopeSegment{
-      name: type_name.clone(),
-    });
+    let TypeSingletonName { name, .. } = type_name;
     //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_name: name.clone(),
             type_args: vec![],
           };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
+          self.values.insert(variant_name.clone(), Symbol { name: variant_name.clone(), 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_name: name.clone(),
             type_args
           };
-          self.add_new_symbol(variant_name, scope_name_stack, spec);
+          let symbol = Symbol { name: variant_name.clone(), spec };
+          self.values.insert(variant_name.clone(), symbol);
         },
-        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);
+        //TODO if there is only one variant, and it is a record, it doesn't need to have an
+        //explicit name
+        Variant::Record { name, members } => {
+          let fields = HashMap::new();
+          let spec = SymbolSpec::RecordConstructor { fields };
+          let symbol = Symbol { name: name.clone(), spec };
+          self.values.insert(name.clone(), symbol);
         },
       }
     }
-    scope_name_stack.pop();
     Ok(())
   }
 }
@@ -340,4 +156,3 @@ impl LocalTypeContext {
     Rc::new(format!("{}", (('a' as u8) + n) as char))
   }
 }
-

schala-lang/language/src/symbol_table/symbol_trie.rs

@@ -1,51 +0,0 @@
-use radix_trie::{Trie, TrieCommon, TrieKey};
-use super::FullyQualifiedSymbolName;
-use std::hash::{Hasher, Hash};
-use std::collections::hash_map::DefaultHasher;
-
-#[derive(Debug)]
-pub struct SymbolTrie(Trie<FullyQualifiedSymbolName, ()>);
-
-impl TrieKey for FullyQualifiedSymbolName {
-  fn encode_bytes(&self) -> Vec<u8> {
-    let mut hasher = DefaultHasher::new();
-    let mut output = vec![];
-    let FullyQualifiedSymbolName(scopes) = self;
-    for segment in scopes.iter() {
-      segment.name.as_bytes().hash(&mut hasher);
-      output.extend_from_slice(&hasher.finish().to_be_bytes());
-    }
-    output
-  }
-}
-
-impl SymbolTrie {
-  pub fn new() -> SymbolTrie {
-    SymbolTrie(Trie::new())
-  }
-
-  pub fn insert(&mut self, fqsn: &FullyQualifiedSymbolName) {
-    self.0.insert(fqsn.clone(), ());
-  }
-
-  pub fn get_children(&self, fqsn: &FullyQualifiedSymbolName) -> Vec<FullyQualifiedSymbolName> {
-    let subtrie = match self.0.subtrie(fqsn) {
-      Some(s) => s,
-      None => return vec![]
-    };
-    let output: Vec<FullyQualifiedSymbolName> = subtrie.keys().filter(|cur_key| **cur_key != *fqsn).map(|fqsn| fqsn.clone()).collect();
-    output
-  }
-}
-
-#[test]
-fn test_trie_insertion() {
-  let mut trie = SymbolTrie::new();
-
-  trie.insert(&fqsn!("unrelated"; ty, "thing"; tr));
-  trie.insert(&fqsn!("outer"; ty, "inner"; tr));
-  trie.insert(&fqsn!("outer"; ty, "inner"; ty, "still_inner"; tr));
-
-  let children = trie.get_children(&fqsn!("outer"; ty, "inner"; tr));
-  assert_eq!(children.len(), 1);
-}

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

@@ -1,193 +0,0 @@
-#![cfg(test)]
-use std::cell::RefCell;
-use std::rc::Rc;
-
-use super::*;
-use crate::util::quick_ast;
-
-fn add_symbols_from_source(src: &str) -> (SymbolTable, Result<(), String>) {
-  let (ast, source_map) = quick_ast(src);
-  let source_map = Rc::new(RefCell::new(source_map));
-  let mut symbol_table = SymbolTable::new(source_map);
-  let result = symbol_table.add_top_level_symbols(&ast);
-  (symbol_table, result)
-}
-
-macro_rules! values_in_table {
-  ($source:expr, $single_value:expr) => {
-    values_in_table!($source => $single_value);
-  };
-  ($source:expr => $( $value:expr ),* ) => {
-    {
-    let (symbol_table, _) = add_symbols_from_source($source);
-    $(
-      match symbol_table.lookup_by_fqsn($value) {
-        Some(_spec) => (),
-        None => panic!(),
-      };
-    )*
-    }
-  };
-}
-
-#[test]
-fn basic_symbol_table() {
-  values_in_table! { "let a = 10; fn b() { 20 }", &fqsn!("b"; tr) };
-  values_in_table! { "type Option<T> = Some(T) | None" =>
-    &fqsn!("Option"; tr),
-    &fqsn!("Option"; ty, "Some"; tr),
-    &fqsn!("Option"; ty, "None"; tr) };
-}
-
-#[test]
-fn no_function_definition_duplicates() {
-  let source = r#"
-  fn a() { 1 }
-  fn b() { 2 }
-  fn a() { 3 }
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate function definition: a"))
-}
-
-#[test]
-fn no_variable_definition_duplicates() {
-  let source = r#"
-  let x = 9
-  let a = 20
-  let q = 39
-  let a = 30
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  let output = output.unwrap_err();
-  assert!(output.contains("Duplicate variable definition: a"));
-  assert!(output.contains("already defined at 2"));
-}
-
-#[test]
-fn no_variable_definition_duplicates_in_function() {
-  let source = r#"
-  fn a() {
-    let a = 20
-    let b = 40
-    a + b
-  }
-
-  fn q() {
-    let a = 29
-    let x = 30
-    let x = 33
-  }
-  "#;
-  let (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate variable definition: x"))
-}
-
-#[test]
-fn dont_falsely_detect_duplicates() {
-  let source = r#"
-  let a = 20;
-  fn some_func() {
-    let a = 40;
-    77
-  }
-  let q = 39;
-  "#;
-  let (symbol_table, _) = add_symbols_from_source(source);
-  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 (symbol_table, _) = add_symbols_from_source(source);
-  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 (symbol_table, _) = add_symbols_from_source(source);
-  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 (_, output) = add_symbols_from_source(source);
-  assert!(output.unwrap_err().contains("Duplicate"))
-}
-
-#[test]
-fn modules() {
-  let source = r#"
-module stuff {
-  fn item() {
-  }
-}
-
-fn item()
-"#;
-  values_in_table! { source  =>
-    &fqsn!("item"; tr),
-    &fqsn!("stuff"; tr, "item"; tr)
-  };
-}
-
-#[test]
-fn duplicate_modules() {
-  let source = r#"
-    module q {
-      fn foo() { 4 }
-    }
-
-    module a {
-      fn foo() { 334 }
-    }
-
-    module a {
-      fn foo() { 256.1 }
-    }
-    "#;
-  let (_, output) = add_symbols_from_source(source);
-  let output = output.unwrap_err();
-  assert!(output.contains("Duplicate module"));
-  assert!(output.contains("already defined at 5"));
-}

schala-lang/language/src/tokenizing.rs

@@ -4,8 +4,6 @@ use std::rc::Rc;
 use std::iter::{Iterator, Peekable};
 use std::fmt;
 
-use crate::source_map::Location;
-
 #[derive(Debug, PartialEq, Clone)]
 pub enum TokenKind {
   Newline, Semicolon,
@@ -17,14 +15,11 @@ pub enum TokenKind {
   Pipe, Backslash,
 
   Comma, Period, Colon, Underscore,
-  Slash, Equals,
+  Slash,
 
   Operator(Rc<String>),
   DigitGroup(Rc<String>), HexLiteral(Rc<String>), BinNumberSigil,
-  StrLiteral {
-    s: Rc<String>,
-    prefix: Option<Rc<String>>
-  },
+  StrLiteral(Rc<String>),
   Identifier(Rc<String>),
   Keyword(Kw),
 
@@ -40,7 +35,7 @@ impl fmt::Display for TokenKind {
       &Operator(ref s) => write!(f, "Operator({})", **s),
       &DigitGroup(ref s) => write!(f, "DigitGroup({})", s),
       &HexLiteral(ref s) => write!(f, "HexLiteral({})", s),
-      &StrLiteral {ref s, .. } => write!(f, "StrLiteral({})", s),
+      &StrLiteral(ref s) => write!(f, "StrLiteral({})", s),
       &Identifier(ref s) => write!(f, "Identifier({})", s),
       &Error(ref s) => write!(f, "Error({})", s),
       other => write!(f, "{:?}", other),
@@ -60,7 +55,7 @@ pub enum Kw {
   Alias, Type, SelfType, SelfIdent,
   Interface, Impl,
   True, False,
-  Module, Import
+  Module
 }
 
 lazy_static! {
@@ -87,14 +82,14 @@ lazy_static! {
       "true" => Kw::True,
       "false" => Kw::False,
       "module" => Kw::Module,
-      "import" => Kw::Import,
     };
 }
 
-#[derive(Debug, Clone, PartialEq)]
+#[derive(Debug, Clone)]
 pub struct Token {
   pub kind: TokenKind,
-  pub location: Location,
+  pub line_num: usize,
+  pub char_num: usize
 }
 
 impl Token {
@@ -105,7 +100,7 @@ impl Token {
     }
   }
   pub fn to_string_with_metadata(&self) -> String {
-    format!("{}({})", self.kind, self.location)
+    format!("{}(L:{},c:{})", self.kind, self.line_num, self.char_num)
   }
 
   pub fn get_kind(&self) -> TokenKind {
@@ -123,7 +118,7 @@ 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))
@@ -166,15 +161,14 @@ pub fn tokenize(input: &str) -> Vec<Token> {
       '(' => LParen, ')' => RParen,
       '{' => LCurlyBrace, '}' => RCurlyBrace,
       '[' => LSquareBracket, ']' => RSquareBracket,
-      '"' => handle_quote(&mut input, None),
+      '"' => 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 is_operator(&c) => handle_operator(c, &mut input),
       unknown => Error(format!("Unexpected character: {}", unknown)),
     };
-    let location = Location { line_num, char_num };
-    tokens.push(Token { kind: cur_tok_kind, location });
+    tokens.push(Token { kind: cur_tok_kind, line_num, char_num });
   }
   tokens
 }
@@ -194,7 +188,7 @@ fn handle_digit(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) ->
   }
 }
 
-fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>, quote_prefix: Option<&str>) -> TokenKind {
+fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
   let mut buf = String::new();
   loop {
     match input.next().map(|(_, _, c)| { c }) {
@@ -216,7 +210,7 @@ fn handle_quote(input: &mut Peekable<impl Iterator<Item=CharData>>, quote_prefix
       None => return TokenKind::Error(format!("Unclosed string")),
     }
   }
-  TokenKind::StrLiteral { s: Rc::new(buf), prefix: quote_prefix.map(|s| Rc::new(s.to_string())) }
+  TokenKind::StrLiteral(Rc::new(buf))
 }
 
 fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
@@ -228,10 +222,6 @@ fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>
 
   loop {
     match input.peek().map(|&(_, _, c)| { c }) {
-      Some(c) if c == '"' => {
-        input.next();
-        return handle_quote(input, Some(&buf));
-      },
       Some(c) if c.is_alphanumeric() || c == '_' => {
         input.next();
         buf.push(c);
@@ -248,7 +238,7 @@ fn handle_alphabetic(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>
 
 fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>) -> TokenKind {
   match c {
-    '<' | '>' | '|' | '.' | '=' => {
+    '<' | '>' | '|' | '.' => {
       let ref next = input.peek().map(|&(_, _, c)| { c });
       if !next.map(|n| { is_operator(&n) }).unwrap_or(false) {
         return match c {
@@ -256,7 +246,6 @@ fn handle_operator(c: char, input: &mut Peekable<impl Iterator<Item=CharData>>)
           '>' => RAngleBracket,
           '|' => Pipe,
           '.' => Period,
-          '=' => Equals,
           _ => unreachable!(),
         }
       }
@@ -309,7 +298,7 @@ mod schala_tokenizer_tests {
     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")]);
+      LAngleBracket, ident!("B"), RAngleBracket, op!("="), ident!("c"), op!("++"), ident!("d")]);
   }
 
   #[test]
@@ -332,13 +321,4 @@ mod schala_tokenizer_tests {
     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")]);
   }
-
-  #[test]
-  fn string_literals() {
-    let token_kinds: Vec<TokenKind> = tokenize(r#""some string""#).into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![StrLiteral { s: Rc::new("some string".to_string()), prefix: None }]);
-
-    let token_kinds: Vec<TokenKind> = tokenize(r#"b"some bytestring""#).into_iter().map(move |t| t.kind).collect();
-    assert_eq!(token_kinds, vec![StrLiteral { s: Rc::new("some bytestring".to_string()), prefix: Some(Rc::new("b".to_string())) }]);
-  }
 }

schala-lang/language/src/typechecking.rs

@@ -1,148 +1,27 @@
 use std::rc::Rc;
-use std::fmt::Write;
-
-use ena::unify::{UnifyKey, InPlaceUnificationTable, UnificationTable, EqUnifyValue};
 
 use crate::ast::*;
 use crate::util::ScopeStack;
-use crate::util::deref_optional_box;
-
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct TypeData {
-  ty: Option<Type>
-}
-
-impl TypeData {
-  #[allow(dead_code)]
-  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>,
+  variable_map: ScopeStack<'a, Rc<String>, Type<TVar>>,
+  evar_count: u32
 }
 
 /// `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 }
+struct TypeError { msg: String }
 
 impl TypeError {
-  fn new<A, T>(msg: T) -> InferResult<A> where T: Into<String> {
-    Err(TypeError { msg: msg.into() })
+  fn new<A>(msg: &str) -> InferResult<A> {
+    Err(TypeError { msg: msg.to_string() })
   }
 }
 
-#[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)]
@@ -225,264 +104,151 @@ impl 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(),
+      evar_count: 0
     }
   }
 
-  /*
-  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)?;
+  pub fn typecheck(&mut self, ast: &AST) -> Result<String, String> {
+    match self.infer_ast(ast) {
+      Ok(t) => Ok(format!("{:?}", t)),
+      Err(err) => Err(format!("Type error: {:?}", err))
     }
-    Ok(returned_type)
+  }
+}
+
+impl<'a> TypeContext<'a> {
+  fn infer_ast(&mut self, ast: &AST) -> InferResult<Type<UVar>> {
+    self.infer_block(&ast.0)
   }
 
-  fn statement(&mut self, statement: &Statement) -> InferResult<Type> {
-    match &statement.kind {
-      StatementKind::Expression(e) => self.expr(e),
-      StatementKind::Declaration(decl) => self.decl(&decl),
-      StatementKind::Import(_) => Ok(ty!(Unit)),
-      StatementKind::Module(_) => Ok(ty!(Unit)),
+  fn infer_statement(&mut self, stmt: &Statement) -> InferResult<Type<UVar>> {
+    match stmt {
+      Statement::ExpressionStatement(ref expr) => self.infer_expr(expr.node()),
+      Statement::Declaration(ref decl) => self.infer_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> {
+  fn infer_expr(&mut self, expr: &Expression) -> InferResult<Type<UVar>> {
     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(expr_type, Some(type_anno)) => {
+        let tx = self.infer_expr_type(expr_type)?;
+        let ty = type_anno.to_monotype();
+        self.unify(&ty.to_tvar(), &tx.to_tvar()).map(|x| x.skolemize())
       },
-      Expression { kind, type_anno: None, .. } => self.expr_type(kind)
+      Expression(expr_type, None) => self.infer_expr_type(expr_type)
     }
   }
 
-  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(deref_optional_box(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 infer_decl(&mut self, _decl: &Declaration) -> InferResult<Type<UVar>> {
+    Ok(Type::Const(TConst::user("unimplemented")))
   }
 
-  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: Option<&Expression>, body: &IfExpressionBody) -> InferResult<Type> {
-    use self::IfExpressionBody::*;
-    match (discriminator, body) {
-      (Some(expr), SimpleConditional{ then_case, else_case }) => self.handle_simple_if(expr, then_case, else_case),
-      _ => 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
+  fn infer_expr_type(&mut self, expr_type: &ExpressionType) -> InferResult<Type<UVar>> {
+    use self::ExpressionType::*;
+    Ok(match expr_type {
+      NatLiteral(_) => Type::Const(TConst::Nat),
+      FloatLiteral(_) => Type::Const(TConst::Float),
+      StringLiteral(_) => Type::Const(TConst::StringT),
+      BoolLiteral(_) => Type::Const(TConst::Bool),
+      Value(name) => {
+        //TODO handle the distinction between 0-arg constructors and variables at some point
+        // need symbol table for that
+        match self.variable_map.lookup(name) {
+          Some(ty) => ty.clone().skolemize(),
+          None => return TypeError::new(&format!("Variable {} not found", name))
         }
-        t_ret.clone()
       },
-      Type::Arrow { .. } => return TypeError::new("Wrong length"),
-      _ => return TypeError::new(format!("Not a function"))
+      IfExpression { discriminator, body } => self.infer_if_expr(discriminator, body)?,
+      Call { f, arguments } => {
+        let tf = self.infer_expr(f)?; //has to be an Arrow Type
+        let targ = self.infer_expr(&arguments[0].node())?; // TODO make this work with functions with more than one arg
+        match tf {
+          Type::Arrow(t1, t2) => {
+            self.unify(&t1.to_tvar(), &targ.to_tvar())?;
+            *t2.clone()
+          },
+          _ => return TypeError::new("not a function")
+        }
+      },
+
+      Lambda { params, .. } => {
+
+        let _arg_type = match &params[0] {
+          (_, Some(type_anno)) => type_anno.to_monotype().to_tvar(),
+          (_, None) => self.allocate_existential(),
+        };
+        //let _result_type = unimplemented!();
+        return TypeError::new("Unimplemented");
+
+        //Type::Arrow(Box::new(arg_type), Box::new(result_type))
+      }
+      _ => Type::Const(TConst::user("unimplemented"))
     })
   }
 
-  fn block(&mut self, block: &Block) -> InferResult<Type> {
-    let mut output = ty!(Unit);
+  fn infer_if_expr(&mut self, discriminator: &Discriminator, body: &IfExpressionBody) -> InferResult<Type<UVar>> {
+    let _test = match discriminator {
+      Discriminator::Simple(expr) => expr,
+      _ => return TypeError::new("Dame desu")
+    };
+
+    let (_then_clause, _maybe_else_clause) = match body {
+      IfExpressionBody::SimpleConditional(a, b) => (a, b),
+      _ => return TypeError::new("Dont work")
+    };
+
+    TypeError::new("Not implemented")
+  }
+
+  fn infer_block(&mut self, block: &Block) -> InferResult<Type<UVar>> {
+    let mut output = Type::Const(TConst::Unit);
     for statement in block.iter() {
-      output = self.statement(statement)?;
+      output = self.infer_statement(statement.node())?;
     }
     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<TVar>, _t2: &Type<TVar>) -> InferResult<Type<TVar>> {
+    TypeError::new("not implemented")
   }
 
-  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
+  fn allocate_existential(&mut self) -> Type<TVar> {
+    let n = self.evar_count;
+    self.evar_count += 1;
+    Type::Var(TVar::Exist(ExistentialVar(n)))
   }
 }
 
 #[cfg(test)]
-mod typechecking_tests {
+mod tests {
   use super::*;
 
-  macro_rules! assert_type_in_fresh_context {
-    ($string:expr, $type:expr) => {
+  fn parse(input: &str) -> AST {
+    let tokens: Vec<crate::tokenizing::Token> = crate::tokenizing::tokenize(input);
+    let mut parser = crate::parsing::Parser::new(tokens);
+    parser.parse().unwrap()
+  }
+
+  macro_rules! type_test {
+    ($input:expr, $correct:expr) => {
+      {
       let mut tc = TypeContext::new();
-      let (ref ast, _) = crate::util::quick_ast($string);
-      let ty = tc.typecheck(ast).unwrap();
-      assert_eq!(ty, $type)
+      let ast = parse($input);
+      tc.add_symbols(&ast);
+      assert_eq!($correct, tc.type_check(&ast).unwrap())
+      }
     }
   }
 
-  #[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));
-    */
+  fn basic_inference() {
+
   }
 }

schala-lang/language/src/util.rs

@@ -1,11 +1,6 @@
 use std::collections::HashMap;
 use std::hash::Hash;
 use std::cmp::Eq;
-use std::ops::Deref;
-
-pub fn deref_optional_box<T>(x: &Option<Box<T>>) -> Option<&T> {
-  x.as_ref().map(|b: &Box<T>| Deref::deref(b))
-}
 
 #[derive(Default, Debug)]
 pub struct ScopeStack<'a, T: 'a, V: 'a>  where T: Hash + Eq {
@@ -46,23 +41,3 @@ impl<'a, T, V> ScopeStack<'a, T, V> where T: Hash + Eq {
   }
 }
 
-/// 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, crate::source_map::SourceMap) {
-  use std::cell::RefCell;
-  use std::rc::Rc;
-
-  let source_map = crate::source_map::SourceMap::new();
-  let source_map_handle = Rc::new(RefCell::new(source_map));
-  let tokens = crate::tokenizing::tokenize(input);
-  let mut parser = crate::parsing::Parser::new(source_map_handle.clone());
-  parser.add_new_tokens(tokens);
-  let output = parser.parse();
-  std::mem::drop(parser);
-  (output.unwrap(), Rc::try_unwrap(source_map_handle).map_err(|_| ()).unwrap().into_inner())
-}
-
-#[allow(unused_macros)]
-macro_rules! rc {
-  ($string:tt) => { Rc::new(stringify!($string).to_string()) }
-}

schala-repl-codegen/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "schala-repl-codegen"
+version = "0.1.0"
+authors = ["greg <greg.shuflin@protonmail.com>"]
+
+[dependencies]
+syn = { version = "0.15.6", features = ["full", "extra-traits"] }
+quote = "0.6.8"
+proc-macro2 = "0.4.19"
+schala-repl = { path = "../schala-repl" }
+
+[lib]
+proc-macro = true

schala-repl-codegen/src/lib.rs

@@ -0,0 +1,199 @@
+#![feature(trace_macros)]
+#![recursion_limit="128"]
+extern crate proc_macro;
+extern crate proc_macro2;
+#[macro_use]
+extern crate quote;
+extern crate syn;
+
+use proc_macro::TokenStream;
+use syn::{Ident, Attribute, DeriveInput};
+
+fn find_attr_by_name<'a>(name: &str, attrs: &'a Vec<Attribute>) -> Option<&'a Attribute> {
+  attrs.iter().find(|attr| {
+    let first = attr.path.segments.first();
+    let seg: Option<&&syn::PathSegment> = first.as_ref().map(|x| x.value());
+    seg.map(|seg| seg.ident.to_string() == name).unwrap_or(false)
+  })
+}
+
+fn extract_attribute_arg_by_name(name: &str, attrs: &Vec<Attribute>) -> Option<String> {
+  use syn::{Meta, Lit, MetaNameValue};
+  find_attr_by_name(name, attrs)
+  .and_then(|attr| {
+    match attr.interpret_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};
+  find_attr_by_name(name, attrs)
+  .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(ref ident)) => (ident.clone(), None),
+          &NestedMeta::Meta(Meta::List(MetaList { ref ident, nested: ref nested2, .. })) => {
+            let own_args = nested2.iter().map(|nested_meta2| match nested_meta2 {
+              &NestedMeta::Meta(Meta::Word(ref ident)) => ident.clone(),
+              _ => panic!("Bad format for doubly-nested attribute list")
+            }).collect();
+            (ident.clone(), Some(own_args))
+          },
+          _ => panic!("Bad format for nested list")
+        }).collect())
+      },
+      _ => panic!("{} must be a comma-delimited list surrounded by parens", name)
+    }
+  })
+}
+
+fn get_attribute_identifier(attr_name: &str, attrs: &Vec<Attribute>) -> Option<proc_macro2::Ident> {
+  find_attr_by_name(attr_name, attrs).and_then(|attr| {
+    let tts = attr.tts.clone().into_iter().collect::<Vec<_>>();
+
+    if tts.len() == 2 {
+      let ref after_equals: proc_macro2::TokenTree = tts[1];
+      match after_equals {
+        proc_macro2::TokenTree::Ident(ident)  => Some(ident.clone()),
+        _ => None
+      }
+    } else {
+      None
+    }
+  })
+}
+
+/* a pass_chain function signature with input A and output B looks like:
+ * fn(A, &mut ProgrammingLanguageInterface, Option<&mut DebugHandler>) -> Result<B, String>
+ *
+ * TODO use some kind of failure-handling library to make this better
+ */
+fn generate_pass_chain(idents: Vec<Ident>) -> proc_macro2::TokenStream {
+  let final_return = quote! {
+    {
+      let final_output: FinishedComputation = unfinished_computation.finish(Ok(input_to_next_stage));
+      final_output
+    }
+  };
+
+  let nested_passes = idents.iter()
+    .rev()
+    .fold(final_return, |later_fragment, pass_name| {
+      quote! {
+        {
+          let pass_name = stringify!(#pass_name);
+          let (output, duration) = {
+            let ref debug_map = eval_options.debug_passes;
+            let debug_handle = match debug_map.get(pass_name) {
+              Some(PassDebugOptionsDescriptor { opts }) => {
+                let ptr = &mut unfinished_computation;
+                ptr.cur_debug_options = opts.clone();
+                Some(ptr)
+              }
+              _ => None
+            };
+            let start = time::Instant::now();
+            let pass_output = #pass_name(input_to_next_stage, self, debug_handle);
+            let elapsed = start.elapsed();
+            (pass_output, elapsed)
+          };
+          if eval_options.debug_timing {
+            unfinished_computation.durations.push(duration);
+          }
+          match output {
+            Ok(input_to_next_stage) => #later_fragment,
+            //TODO this error type needs to be guaranteed to provide a useable string
+            Err(err) => return unfinished_computation.output(Err(format!("Pass {} failed:\n{}", pass_name, err))),
+          }
+        }
+      }
+    });
+
+  quote! {
+    {
+      use std::time;
+      use schala_repl::PassDebugOptionsDescriptor;
+
+      let eval_options = options;
+      let input_to_next_stage = input;
+      let mut unfinished_computation = UnfinishedComputation::default();
+      #nested_passes
+    }
+  }
+}
+
+#[proc_macro_derive(ProgrammingLanguageInterface,
+  attributes(LanguageName, SourceFileExtension, PipelineSteps, DocMethod, HandleCustomInterpreterDirectives))]
+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.clone());
+
+  let get_doc_impl = match get_attribute_identifier("DocMethod", attrs) {
+    None => quote! { },
+    Some(method_name) => quote! {
+      fn get_doc(&self, commands: &Vec<&str>) -> Option<String> {
+        self.#method_name(commands)
+      }
+    }
+  };
+
+  let handle_custom_interpreter_directives_impl = match get_attribute_identifier("HandleCustomInterpreterDirectives", attrs) {
+    None => quote! { },
+    Some(method_name) => quote! {
+      fn handle_custom_interpreter_directives(&mut self, commands: &Vec<&str>) -> Option<String> {
+        //println!("If #method_name is &self not &mut self, this runs forever");
+        self.#method_name(commands)
+      }
+    }
+  };
+
+  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 pass_chain = generate_pass_chain(pass_idents.collect());
+
+  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 {
+        #pass_chain
+      }
+      fn get_passes(&self) -> Vec<PassDescriptor> {
+        vec![ #(#pass_descriptors),* ]
+      }
+      #get_doc_impl
+      #handle_custom_interpreter_directives_impl
+    }
+  };
+
+  let output: TokenStream = tokens.into();
+  output
+}

schala-repl/Cargo.toml

@@ -2,22 +2,23 @@
 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"
 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 = "0.4.0"
+rocket_contrib = "0.4.0"
 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 +1,173 @@
+use std::collections::HashMap;
+use colored::*;
+use std::fmt::Write;
 use std::time;
-use std::collections::HashSet;
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct EvalOptions {
+  pub execution_method: ExecutionMethod,
+  pub debug_passes: HashMap<String, PassDebugOptionsDescriptor>,
+  pub debug_timing: bool,
+}
+
+#[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 {
+
+  fn get_timing(&self) -> Option<String> {
+    if self.durations.len() != 0 {
+      let mut buf = String::new();
+      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();
+      Some(buf)
+    } else {
+      None
+    }
+  }
+
+  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();
+    }
+
+    match self.get_timing() {
+      Some(timing) => write!(&mut buf, "{}", timing).unwrap(),
+      None => ()
+    }
+
+    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 run_computation(&mut self, _request: ComputationRequest) -> ComputationResponse {
-    ComputationResponse {
-      main_output: Err(format!("Computation pipeline not implemented")),
-      global_output_stats: GlobalOutputStats::default(),
-      debug_responses: vec![],
-    }
+  fn get_passes(&self) -> Vec<PassDescriptor> {
+    vec![]
   }
-
-  fn request_meta(&mut self, _request: LangMetaRequest) -> LangMetaResponse {
-    LangMetaResponse::Custom { kind: format!("not-implemented"), value: format!("") }
+  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 get_doc(&self, _commands: &Vec<&str>) -> Option<String> {
+    None
   }
 }
-
-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
-    }
-  }
-}
-
-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),
-}

schala-repl/src/lib.rs

@@ -1,4 +1,5 @@
-#![feature(link_args, box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
+#![feature(link_args)]
+#![feature(slice_patterns, box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
 #![feature(plugin)]
 extern crate getopts;
 extern crate linefeed;
@@ -8,49 +9,88 @@ extern crate colored;
 #[macro_use]
 extern crate serde_derive;
 extern crate serde_json;
+#[macro_use]
+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::process::exit;
+use std::default::Default;
 
 mod repl;
 mod language;
+mod webapp;
 
-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::{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::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");
@@ -64,28 +104,53 @@ 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));
+    }
+  }
 }
 
-
-fn command_line_options() -> getopts::Options {
+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/repl/command_tree.rs

@@ -1,34 +1,23 @@
-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,
+    function: Option<Box<(fn() -> Option<String>)>>,
   },
   NonTerminal {
     name: String,
     children: Vec<CommandTree>,
     help_msg: Option<String>,
-    action: DirectiveAction,
+    function: Option<Box<(fn() -> Option<String>)>>,
   },
   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 term(s: &str, help: Option<&str>) -> CommandTree {
+    CommandTree::Terminal {name: s.to_string(), help_msg: help.map(|x| x.to_string()), function: None }
   }
 
   pub fn nonterm(s: &str, help: Option<&str>, children: Vec<CommandTree>) -> CommandTree {
@@ -36,7 +25,7 @@ impl CommandTree {
       name: s.to_string(),
       help_msg: help.map(|x| x.to_string()),
       children,
-      action: DirectiveAction::Null
+      function: None,
     }
   }
 
@@ -49,51 +38,16 @@ impl CommandTree {
   }
   pub fn get_help(&self) -> &str {
     match self {
-      CommandTree::Terminal { help_msg, ..} => help_msg.as_ref().map(|s| s.as_str()).unwrap_or("<no help text provided>"),
-      CommandTree::NonTerminal { help_msg, .. } => help_msg.as_ref().map(|s| s.as_str()).unwrap_or("<no help text provided>"),
+      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::*;
+  pub fn get_children(&self) -> Vec<&str> {
     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())
+      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(),
     }
   }
 }

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

@@ -1,59 +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();
-          let cmd = dir.get_cmd();
-          let children = dir.get_children();
-          writeln!(buf, "`{}` - {}", cmd, dir.get_help()).unwrap();
-          for sub in children.iter() {
-            writeln!(buf, "\t`{} {}` - {}", cmd, sub.get_cmd(), sub.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

@@ -1,193 +1,324 @@
+use std::fmt::Write as FmtWrite;
+use std::io::{Read, Write};
+use std::fs::File;
 use std::sync::Arc;
-use std::collections::HashSet;
-
-use crate::language::{ProgrammingLanguageInterface,
-ComputationRequest, LangMetaResponse, LangMetaRequest};
 
+use colored::*;
+use itertools::Itertools;
+use language::{ProgrammingLanguageInterface, EvalOptions,
+  PassDebugOptionsDescriptor};
 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,
+  options: EvalOptions,
+  languages: Vec<Box<ProgrammingLanguageInterface>>,
+  current_language_index: usize,
+  interpreter_directive_sigil: char,
   line_reader: ::linefeed::interface::Interface<::linefeed::terminal::DefaultTerminal>,
-  language_states: Vec<Box<dyn ProgrammingLanguageInterface>>,
-  options: ReplOptions,
-}
-
-#[derive(Clone)]
-enum PromptStyle {
-  Normal,
-  Multiline
 }
 
 impl Repl {
-  pub fn new(initial_states: Vec<Box<dyn ProgrammingLanguageInterface>>) -> Repl {
+  pub fn new(languages: Vec<Box<ProgrammingLanguageInterface>>, initial_index: usize) -> Repl {
     use linefeed::Interface;
+    let current_language_index = if initial_index < languages.len() { initial_index } else { 0 };
+
     let line_reader = Interface::new("schala-repl").unwrap();
-    let interpreter_directive_sigil = ':';
 
     Repl {
-      interpreter_directive_sigil,
+      options: Repl::get_options(),
+      languages,
+      current_language_index,
+      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);
+  fn get_cur_language(&self) -> &ProgrammingLanguageInterface {
+    self.languages[self.current_language_index].as_ref()
+  }
+
+  fn get_options() -> EvalOptions {
+    File::open(OPTIONS_SAVE_FILE)
+      .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(OPTIONS_SAVE_FILE)
+      .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 {} file {}", OPTIONS_SAVE_FILE, err);
+    }
+  }
+
+  pub 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.load_options();
-    self.handle_repl_loop();
-    self.save_before_exit();
+
+    self.line_reader.load_history(HISTORY_SAVE_FILE).unwrap_or(());
+
+    loop {
+      let language_name = self.get_cur_language().get_language_name();
+      let directives = self.get_directives();
+      let tab_complete_handler = TabCompleteHandler::new(self.interpreter_directive_sigil, directives);
+      self.line_reader.set_completer(Arc::new(tab_complete_handler));
+
+      let prompt_str = format!("{} >> ", language_name);
+      self.line_reader.set_prompt(&prompt_str).unwrap();
+
+      match self.line_reader.read_line() {
+        Err(e) => {
+          println!("Terminal read error: {}", e);
+        },
+        Ok(ReadResult::Eof) => break,
+        Ok(ReadResult::Signal(_)) => break,
+        Ok(ReadResult::Input(input)) => self.input_loop(input),
+      }
+    }
+    self.line_reader.save_history(HISTORY_SAVE_FILE).unwrap_or(());
+    self.save_options();
     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 input_loop(&mut self, input: String) {
+    use linefeed::ReadResult;
+    if input == "" {
+      return;
+    }
 
-  fn handle_repl_loop(&mut self) {
-    use linefeed::ReadResult::*;
-    let sigil = self.interpreter_directive_sigil;
+    if input.chars().nth(0).unwrap() == self.interpreter_directive_sigil {
+      if let Some(output) = self.handle_interpreter_directive(&input) {
+        println!("{}", output);
+      }
+      return;
+    } 
 
-    'main: loop {
-      macro_rules! match_or_break {
-        ($line:expr) => {
-          match $line {
-            Err(e) => {
-              println!("readline IO Error: {}", e);
-              break 'main;
-            },
-            Ok(Eof) | Ok(Signal(_)) => break 'main,
-            Ok(Input(ref input)) => input,
-          }
+    let mut lines = input;
+    self.line_reader.set_prompt("> ").unwrap();
+
+    loop {
+      match self.line_reader.read_line() {
+        Err(e) => {
+          println!("Terminal read error: {}", e);
+          return;
+        },
+        Ok(ReadResult::Eof) => break,
+        Ok(ReadResult::Signal(_)) => break,
+        Ok(ReadResult::Input(input)) => {
+          lines.push('\n'); //TODO not sure if this is needed?
+          lines.push_str(&input);
         }
       }
-      self.update_line_reader();
-      let line = self.line_reader.read_line();
-      let input: &str = match_or_break!(line);
-
-      self.line_reader.add_history_unique(input.to_string());
-      let mut chars = input.chars().peekable();
-      let repl_responses = match chars.nth(0) {
-        Some(ch) if ch == sigil => {
-          if chars.peek() == Some(&'{') {
-            let mut buf = String::new();
-            buf.push_str(input.get(2..).unwrap());
-            'multiline: loop {
-              self.set_prompt(PromptStyle::Multiline);
-              let new_line = self.line_reader.read_line();
-              let new_input = match_or_break!(new_line);
-              if new_input.starts_with(":}") {
-                break 'multiline;
-              } else {
-                buf.push_str(new_input);
-                buf.push_str("\n");
-              }
-            }
-            self.handle_input(&buf)
-          } else {
-            match self.handle_interpreter_directive(input) {
-              Some(directive_output) => println!("<> {}", directive_output),
-              None => (),
-            }
-            continue
-          }
-        },
-        _ => self.handle_input(input)
-      };
-
-      for repl_response in repl_responses.iter() {
-        println!("{}", repl_response);
-      }
     }
+
+    self.line_reader.add_history_unique(lines.clone());
+    let output = self.input_handler(&lines);
+    println!("=> {}", output);
   }
 
-  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
-    self.set_prompt(PromptStyle::Normal);
+  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 set_prompt(&mut self, prompt_style: PromptStyle) {
-    let prompt_str = match prompt_style {
-      PromptStyle::Normal => ">> ".to_string(),
-      PromptStyle::Multiline => ">| ".to_string(),
-    };
+  fn get_directives(&self) -> CommandTree {
+    let ref passes = self.get_cur_language().get_passes();
 
-    self.line_reader.set_prompt(&prompt_str).unwrap();
+    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 children: Vec<CommandTree> = pass_descriptor.debug_options.iter()
+            .map(|o| CommandTree::term(o, None)).collect();
+          CommandTree::NonTerminal {
+            name: name.clone(),
+            children,
+            help_msg: None,
+            function: 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::nonterm("debug",
+        Some("show or hide pass debug info for a given pass, or display the names of all passes, or turn timing on/off"),
+        vec![
+          CommandTree::term("passes", None),
+          CommandTree::nonterm("show", None, passes_directives.clone()),
+          CommandTree::nonterm("hide", None, passes_directives.clone()),
+          CommandTree::nonterm("timing", None, vec![
+            CommandTree::term("on", None),
+            CommandTree::term("off", None),
+          ])
+        ]
+      ),
+      CommandTree::nonterm("lang",
+        Some("switch between languages, or go directly to a langauge by name"),
+        vec![
+          CommandTree::term("next", None),
+          CommandTree::term("prev", None),
+          CommandTree::nonterm("go", None, vec![]),
+        ]
+      ),
+      CommandTree::term("doc", Some("Get language-specific help for an item")),
+    ])
   }
 
-  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 {
+  fn handle_interpreter_directive(&mut self, input: &str) -> Option<String> {
     let mut iter = input.chars();
     iter.next();
-    let arguments: Vec<&str> = iter
+    let commands: 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![],
+    let initial_cmd: &str = match commands.get(0).clone() {
+      None => return None,
+      Some(s) => s
     };
 
-    directives_from_pass_names(&pass_names)
+    match initial_cmd {
+      "exit" | "quit"  => {
+        self.save_options();
+        ::std::process::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),
+      "doc" => self.languages[self.current_language_index]
+        .get_doc(&commands)
+        .or(Some(format!("No docs implemented"))),
+      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(&"timing") => match commands.get(2) {
+        Some(&"on") => { self.options.debug_timing = true; None }
+        Some(&"off") => { self.options.debug_timing = false; None }
+        _ => return Some(format!(r#"Argument to "timing" must be "on" or "off""#)),
+      },
+      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"))
+    }
   }
 }
 
-
 struct TabCompleteHandler {
   sigil: char,
   top_level_commands: CommandTree,
@@ -209,43 +340,43 @@ 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;
-    }
+    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);
 
-    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(' ')
-              })
+      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.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 { .. } => None,
+            });
+            command_tree = new_ptr;
           }
-          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)
+    } else {
+      None
     }
-    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::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);
 }