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pkg/analyzer/lib/src/generated/constant.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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.constant;
 
 import 'dart:collection';
@@ skipping 593 matching lines @@
       // The name either doesn't exist in the environment or we couldn't parse the corresponding
       // value.  If the code supplied an explicit default, use it.
       if (namedArgumentValues.containsKey(_DEFAULT_VALUE_PARAM)) {
         value = namedArgumentValues[_DEFAULT_VALUE_PARAM];
       } else if (value.isNull) {
         // The code didn't supply an explicit default.  The name exists in the environment but
         // we couldn't parse the corresponding value.  So use the built-in default value, because
         // this is what the VM does.
         value = builtInDefaultValue;
       } else {
+        // The code didn't supply an explicit default.  The name doesn't exist in the environment.
+        // The VM would use the built-in default value, but we don't want to do that for analysis
+        // because it's likely to lead to cascading errors.  So just leave [value] in the unknown
+        // state.
       }
     }
     return value;
   }
 
   DartObjectImpl _evaluateConstructorCall(AstNode node, NodeList<Expression> arguments, ConstructorElement constructor, ConstantVisitor constantVisitor, ErrorReporter errorReporter) {
     int argumentCount = arguments.length;
     List<DartObjectImpl> argumentValues = new List<DartObjectImpl>(argumentCount);
     HashMap<String, DartObjectImpl> namedArgumentValues = new HashMap<String, DartObjectImpl>();
     for (int i = 0; i < argumentCount; i++) {
@@ skipping 182 matching lines @@
 
   /**
    * Generate an error indicating that the given constant is not a valid compile-time constant
    * because it references at least one of the constants in the given cycle, each of which directly
    * or indirectly references the constant.
    *
    * @param constantsInCycle the constants in the cycle that includes the given constant
    * @param constant the constant that is not a valid compile-time constant
    */
   void _generateCycleError(List<AstNode> constantsInCycle, AstNode constant) {
+    // TODO(brianwilkerson) Implement this.
   }
 
   ConstructorElement _getConstructorBase(ConstructorElement constructor) {
     while (constructor is ConstructorMember) {
       constructor = (constructor as ConstructorMember).baseElement;
     }
     return constructor;
   }
 }
 
@@ skipping 3737 matching lines @@
 
   @override
   String get typeName => "Type";
 
   @override
   int get hashCode => _element == null ? 0 : _element.hashCode;
 
   @override
   String toString() => _element == null ? "-unknown-" : _element.name;
 }