More typechecking infrastructure

schala-lang/language/src/typechecking.rs

@@ -1,6 +1,6 @@
 use std::rc::Rc;
 
-use ast::AST;
+use ast::*;
 
 pub type TypeName = Rc<String>;
 
@@ -8,12 +8,39 @@ pub struct TypeContext {
 
 }
 
+type TypeResult<T> = Result<T, TypeError>;
+
+#[derive(Debug, Clone)]
+struct TypeError { }
+
+struct Type {
+
+}
+
 impl TypeContext {
   pub fn new() -> TypeContext {
     TypeContext { }
   }
 
-  pub fn typecheck(&mut self, _ast: &AST) -> Result<(), String> {
+  pub fn typecheck(&mut self, ast: &AST) -> Result<(), String> {
-    Ok(())
+    match self.infer_ast(ast) {
+      Ok(_) => Ok(()),
+      Err(err) => Err(format!("Type error: {:?}", err))
+    }
+  }
+}
+
+impl TypeContext {
+  fn infer_ast(&mut self, ast: &AST) -> TypeResult<()> {
+    unimplemented!()
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+  #[test]
+  fn basic_inference() {
+
   }
 }