Remove string constants from Types class.

dart/lib/compiler/implementation/typechecker.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.
 
 class TypeCheckerTask extends CompilerTask {
   TypeCheckerTask(Compiler compiler) : super(compiler);
   String get name() => "Type checker";
 
   static final bool LOG_FAILURES = false;
 
@@ skipping 44 matching lines @@
   /** Combine the information about two control-flow edges that are joined. */
   StatementType join(StatementType other) {
     return (this === other) ? this : MAYBE_RETURNING;
   }
 
   String toString() => stringName;
 }
 
 class VoidType implements Type {
   const VoidType(this.element);
-  SourceString get name() => Types.VOID;
+  SourceString get name() => element.name;
   final VoidElement element;
 
   toString() => name.slowToString();
 }
 
 class InterfaceType implements Type {
   final Element element;
   final Link<Type> arguments;
 
   const InterfaceType(this.element,
@@ skipping 33 matching lines @@
   SourceString get name() => const SourceString('Function');
 
   int computeArity() {
     int arity = 0;
     parameterTypes.forEach((_) { arity++; });
     return arity;
   }
 }
 
 class Types {
-  static final VOID = const SourceString('void');
-  static final INT = const SourceString('int');
-  static final DOUBLE = const SourceString('double');
-  static final DYNAMIC = const SourceString('Dynamic');
-  static final STRING = const SourceString('String');
-  static final BOOL = const SourceString('bool');
-  static final OBJECT = const SourceString('Object');
-  static final LIST = const SourceString('List');
-
   final VoidType voidType;
   final InterfaceType dynamicType;
 
   Types(Element dynamicElement)
     : this.with(dynamicElement, new LibraryElement(new Script(null, null)));
 
   // TODO(karlklose): should we have a class Void?
   Types.with(Element dynamicElement, LibraryElement library)
     : voidType = new VoidType(new VoidElement(library)),
       dynamicType = new InterfaceType(dynamicElement);
 
-  Type lookup(SourceString s) {
-    if (VOID == s) {
-      return voidType;
-    } else if (DYNAMIC == s || s.stringValue === 'var') {
-      return dynamicType;
-    }
-    return null;
-  }
-
   /** Returns true if t is a subtype of s */
   bool isSubtype(Type t, Type s) {
     if (t === s || t === dynamicType || s === dynamicType ||
-        s.name == OBJECT) return true;
+        // TODO(karlklose): Test for s.element === compiler.objectClass.
+        s.name == const SourceString('Object')) return true;
     if (t is VoidType) {
       return false;
     } else if (t is InterfaceType) {
       if (s is !InterfaceType) return false;
       ClassElement tc = t.element;
       if (tc === s.element) return true;
       for (Link<Type> supertypes = tc.allSupertypes;
            supertypes != null && !supertypes.isEmpty();
            supertypes = supertypes.tail) {
         Type supertype = supertypes.head;
@@ skipping 623 matching lines @@
   }
 
   visitCatchBlock(CatchBlock node) {
     return unhandledStatement();
   }
 
   visitTypedef(Typedef node) {
     return unhandledStatement();
   }
 }