Use the typedef arity to know how to invoke a closure given by the dom.

dart/lib/compiler/implementation/elements/elements.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #library('elements');
 
 #import('../tree/tree.dart');
 #import('../scanner/scannerlib.dart');
 #import('../leg.dart');  // TODO(karlklose): we only need type.
 #import('../util/util.dart');
@@ skipping 336 matching lines @@
       super(prefix, ElementKind.PREFIX, enclosing);
 
   lookupLocalMember(SourceString memberName) => imported[memberName];
 
   Type computeType(Compiler compiler) => compiler.types.dynamicType;
 
   Token position() => firstPosition;
 }
 
 class TypedefElement extends Element {
-  final Token token;
   Type cachedType;
+  Typedef cachedNode;
 
-  TypedefElement(SourceString name, Element enclosing, this.token)
-      : super(name, ElementKind.TYPEDEF, enclosing) {
-    cachedType = new InterfaceType(this);
+  TypedefElement(SourceString name, Element enclosing)
+      : super(name, ElementKind.TYPEDEF, enclosing);
+
+  Type computeType(Compiler compiler) {
+    if (cachedType !== null) return cachedType;
+    cachedType = compiler.computeFunctionType(
+        this, compiler.resolveTypedef(this));
+    return cachedType;
   }
-
-  position() => findMyName(token);

[ahe, 2012/05/29 15:43:49]

Did you mean to delete this?

[ngeoffray, 2012/05/29 15:51:42]

Yes, it is now in PartialTypedefElement.

-
-  Type computeType(Compiler compiler) => cachedType;
 }
 
 class VariableElement extends Element {
   final VariableListElement variables;
   Expression cachedNode; // The send or the identifier in the variables list.
 
   Modifiers get modifiers() => variables.modifiers;
 
   VariableElement(SourceString name,
                   VariableListElement this.variables,
@@ skipping 226 matching lines @@
   int optionalParameterCount(Compiler compiler) {
     return computeSignature(compiler).optionalParameterCount;
   }
 
   int parameterCount(Compiler compiler) {
     return computeSignature(compiler).parameterCount;
   }
 
   FunctionType computeType(Compiler compiler) {
     if (type != null) return type;
-    compiler.withCurrentElement(this, () {
-      FunctionSignature signature = computeSignature(compiler);
-      LinkBuilder<Type> parameterTypes = new LinkBuilder<Type>();
-      for (Link<Element> link = signature.requiredParameters;
-           !link.isEmpty();
-           link = link.tail) {
-         parameterTypes.addLast(link.head.computeType(compiler));
-         // TODO(karlklose): optional parameters.
-      }
-      type = new FunctionType(signature.returnType,
-                              parameterTypes.toLink(),
-                              this);
-    });
+    type = compiler.computeFunctionType(this, computeSignature(compiler));
     return type;
   }
 
   Node parseNode(DiagnosticListener listener) => cachedNode;
 
   Token position() => cachedNode.getBeginToken();
 }
 
 class ConstructorBodyElement extends FunctionElement {
   FunctionElement constructor;
@@ skipping 409 matching lines @@
   final Node node;
   Type bound;
   Type type;
   TypeVariableElement(name, Element enclosing, this.node, this.type,
                       [this.bound])
     : super(name, ElementKind.TYPE_VARIABLE, enclosing);
   Type computeType(compiler) => type;
   Node parseNode(compiler) => node;
   toString() => "${enclosingElement.toString()}.${name.slowToString()}";
 }