anchor.diff:              // So the value of the variable is still available for debugging
               // purposes we convert the constant variable to be a final variable
               // initialized to the evaluated constant expression.
  -            node.initializer = new ConstantExpression(constant)..parent = node;
  +            node.initializer = makeConstantExpression(constant)..parent = node;
               node.isFinal = true;
               node.isConst = false;
             } else {
  
positive.code:     return constantEvaluator.runInsideContext(treeContext, () {
        return constantEvaluator.evaluate(node);
      });
    }
  }
  
  
negative.code: 
    tryEvaluateAndTransformWithContext(TreeNode treeContext, Expression node) {
      final Constant constant = tryEvaluateWithContext(treeContext, node);
      return constant != null ? makeConstantExpression(constant) : node;
    }
  
    tryEvaluateWithContext(TreeNode treeContext, Expression node) {
  