anchor.diff:  /** 
    * Instance of a `ClassElement` is our abstract representation of the class.
    **/
  -class ClassElement extends NamedElement with Block {
  +class ClassElement extends Block implements NamedElement {
     Map<Name, FieldElement> declaredFields = <Name, FieldElement>{};
     Map<Name, MethodElement> declaredMethods = <Name, MethodElement>{};
     Map<Name, ConstructorElement> declaredConstructors = <Name, ConstructorElement>{};
  
positive.code:   bool get isSetter => ast.isSetter;
    bool get isStatic => ast.isStatic;
    bool get isSynthetic => ast.isSynthetic;
    
    TypeName get returnType => ast.returnType;
    FormalParameterList get parameters => ast.parameters;
  
negative.code:  * Instances of the class `Block` represents a static scope of the program. 
   * it could be a Library, a Class, a Method etc.
   * **/ 
  abstract class Block extends Element {
    Block enclosingBlock = null;
    List<Block> nestedBlocks = <Block>[];
    
  