Start AST-reducing

schala-lang/src/ast_reducing.rs

@@ -1,9 +1,11 @@
 use std::rc::Rc;
 
-use parsing::AST;
+use parsing::{AST, Expression, Declaration};
 
+#[derive(Debug)]
 pub struct ReducedAST(pub Vec<Stmt>);
 
+#[derive(Debug)]
 pub enum Stmt {
   Binding {
     name: Rc<String>,
@@ -12,6 +14,7 @@ pub enum Stmt {
   Expr(Expr),
 }
 
+#[derive(Debug)]
 pub enum Expr {
   Literal(Lit),
   Func(Func),
@@ -21,18 +24,34 @@ pub enum Expr {
   },
 }
 
+#[derive(Debug)]
 pub enum Lit {
   Int(u64),
   Bool(bool),
   StringLit(Rc<String>),
 }
 
+#[derive(Debug)]
 pub struct Func {
   params: Vec<Rc<String>>,
   body: Vec<Stmt>,
 }
 
-
-pub fn perform_ast_reduction(input: &AST) -> Result<ReducedAST, String> {
-  Ok(ReducedAST(vec![]))
+pub fn perform_ast_reduction(ast: &AST) -> Result<ReducedAST, String> {
+  use parsing::Statement::*;
+  let mut output = vec![];
+  for statement in ast.0.iter() {
+    match statement {
+      &ExpressionStatement(ref expr) => output.push(reduce_expr(expr)?),
+      &Declaration(ref decl) => output.push(reduce_decl(decl)?),
+    }
+  }
+  Ok(ReducedAST(output))
+}
+
+fn reduce_expr(expr: &Expression) -> Result<Stmt, String> {
+  Ok(Stmt::Expr(Expr::Literal(Lit::Int(0))))
+}
+fn reduce_decl(expr: &Declaration) -> Result<Stmt, String> {
+  Ok(Stmt::Expr(Expr::Literal(Lit::Int(0))))
 }

schala-lang/src/lib.rs

@@ -95,6 +95,7 @@ fn typechecking(handle: &mut Schala, input: parsing::AST, comp: Option<&mut Unfi
 type TempASTReduction = (ast_reducing::ReducedAST, parsing::AST);
 fn ast_reducing(handle: &mut Schala, input: parsing::AST, comp: Option<&mut UnfinishedComputation>) -> Result<TempASTReduction, String> {
   let output = ast_reducing::perform_ast_reduction(&input)?;
+  println!("REDUCED: {:?}", output);
   Ok((output, input))
 }