Typechecking infrastructure

schala-lang/language/src/lib.rs

@@ -43,6 +43,7 @@ mod eval;
 pub struct Schala {
   state: eval::State<'static>,
   symbol_table: Rc<RefCell<symbol_table::SymbolTable>>,
+  type_context: typechecking::TypeContext,
   active_parser: Option<parsing::Parser>,
 }
 
@@ -62,6 +63,7 @@ impl Schala {
     Schala {
       symbol_table: symbols.clone(),
       state: eval::State::new(symbols),
+      type_context: typechecking::TypeContext::new(),
       active_parser: None,
     }
   }
@@ -126,8 +128,9 @@ fn symbol_table(handle: &mut Schala, input: ast::AST, comp: Option<&mut Unfinish
   }
 }
 
-fn typechecking(_handle: &mut Schala, input: ast::AST, _comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
-  Ok(input)
+fn typechecking(handle: &mut Schala, input: ast::AST, _comp: Option<&mut UnfinishedComputation>) -> Result<ast::AST, String> {
+
+  handle.type_context.typecheck(&input).map(|_| input)
 }
 
 fn ast_reducing(handle: &mut Schala, input: ast::AST, comp: Option<&mut UnfinishedComputation>) -> Result<reduced_ast::ReducedAST, String> {

schala-lang/language/src/typechecking.rs

@@ -1,3 +1,19 @@
 use std::rc::Rc;
 
+use ast::AST;
+
 pub type TypeName = Rc<String>;
+
+pub struct TypeContext {
+
+}
+
+impl TypeContext {
+  pub fn new() -> TypeContext {
+    TypeContext { }
+  }
+
+  pub fn typecheck(&mut self, _ast: &AST) -> Result<(), String> {
+    Ok(())
+  }
+}