Towards compiling Hello World!

pkg/compiler/lib/src/constants/expressions.dart

 // Copyright (c) 2014, 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 dart2js.constants.expressions;
 
 import '../common.dart';
 import '../constants/constant_system.dart';
 import '../common_elements.dart';
 import '../elements/entities.dart';
@@ skipping 720 matching lines @@
       commonElements.symbolType;
 }
 
 /// Type literal.
 class TypeConstantExpression extends ConstantExpression {
   /// Either [DynamicType] or a raw [GenericType].
   final DartType type;
   final String name;
 
   TypeConstantExpression(this.type, this.name) {
-    assert(type.isInterfaceType ||
-        type.isTypedef ||
-        type.isFunctionType ||
-        type.isDynamic);
+    assert(
+        type.isInterfaceType ||
+            type.isTypedef ||
+            type.isFunctionType ||
+            type.isDynamic,
+        "Unexpected type constant type: $type");
   }
 
   ConstantExpressionKind get kind => ConstantExpressionKind.TYPE;
 
   accept(ConstantExpressionVisitor visitor, [context]) {
     return visitor.visitType(this, context);
   }
 
   @override
   void _createStructuredText(StringBuffer sb) {
@@ skipping 1170 matching lines @@
     visit(exp.name);
     if (exp.defaultValue != null) {
       sb.write(', defaultValue: ');
       visit(exp.defaultValue);
     }
     sb.write(')');
   }
 
   String toString() => sb.toString();
 }