anchor.diff:    
     @override
     visitClassDeclaration(ClassDeclaration node){
  -    
       _openNewScope(scope, (_) {
         Our.ClassElement c = this.declaredElements[node];
   
  
positive.code:   Engine engine;
    Our.ClassElement _currentClass = null;
  
    ScopeVisitor(this.engine, this.declaredElements, this.references, this.library) {
      this.scope = {};
    }
  
  
negative.code:       }
      }
    }
    */
  
    @override
    visitMethodInvocation(MethodInvocation node) {
  