More visitor stuff

TODO.md

@@ -7,7 +7,7 @@
 - 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,
-                                2) the non-value-returning, default one like in rustc
+                                2) the non-value-returning, default one like in rustc (cf. https://github.com/rust-unofficial/patterns/blob/master/patterns/visitor.md)
 
 ## Reduction
  - make a good type for actual language builtins to avoid string comparisons

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

@@ -48,9 +48,15 @@ pub trait ASTVisitor: Sized {
     walker::maybe_type_identifier(self, type_anno);
   }
 
-  fn import(&mut self, import: &ImportSpecifier) {
+  fn named_struct(&mut self, name: &QualifiedName, fields: &Vec<(Rc<String>, Expression)>) {
+    self.qualified_name(name);
+    for (_, expr) in fields.iter() {
+      walker::expression(self, expr);
+    }
   }
 
+  fn import(&mut self, import: &ImportSpecifier) {}
+  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>) {}

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

@@ -69,15 +69,16 @@ pub fn expression_kind<V: ASTVisitor>(v: &mut V, expression_kind: &ExpressionKin
     BoolLiteral(b) => v.bool_literal(*b),
     BinExp(op, lhs, rhs) => v.binexp(op, lhs, rhs),
     PrefixExp(op, arg) => v.prefix_exp(op, arg),
+    TupleLiteral(exprs) => {
+      for expr in exprs {
+        v.expression(expr);
+      }
+    },
+    Value(name) => v.qualified_name(name),
+    NamedStruct { name, fields } => v.named_struct(name, fields),
     _ => (),
   }
     /*
-  TupleLiteral(Vec<Expression>),
-  Value(QualifiedName),
-  NamedStruct {
-    name: QualifiedName,
-    fields: Vec<(Rc<String>, Expression)>,
-  },
   Call {
     f: Box<Expression>,
     arguments: Vec<InvocationArgument>,
@@ -109,4 +110,3 @@ pub fn expression_kind<V: ASTVisitor>(v: &mut V, expression_kind: &ExpressionKin
   */
 }
 
-