anchor.diff:          classBody
       ;
   
  +objectDeclaration
  +    :
  +        'object'!
  +        memberName
  +        extendedType?
  +        satisfiedTypes?
  +        classBody
  +    ;
  +
  +caseDeclaration
  +    : 
  +        'case'!
  +        memberName 
  +        argumentsWithFunctionalArguments 
  +        ';'!
  +    ;
  +
   classBody
       : '{' declarationOrStatement* '}'
       -> ^(STMT_LIST declarationOrStatement*)
  
positive.code:     IMPORT_WILDCARD;
      IMPORT_PATH;
      INIT_EXPR;
      INST_DECL;
      INTERFACE_DECL;
      MEMBER_NAME;
      MEMBER_TYPE;
  
negative.code:     : 'local' 
      | 'assign' 
      | 'void' 
      | 'case'
      | 'object'
      | 'class' 
      | 'interface' 
      | 'alias'
  