anchor.diff:          this.name == other.name &&
           this.library == other.library;
     }
  -
  -  @override
  -  int get hashCode {
  -    return name.hashCode ^ library.hashCode;
  -  }
   }
  
positive.code:   final String library;
  
    InterfaceTypeDefinition(this.name, this.library);
  
    @override
    bool operator ==(Object other) {
  
negative.code:     }
      return false;
    }
  }
  
  class InterfaceTypeDefinition {
  