anchor.diff:      | 'set'
       | 'vararg'
       | 'where'
  +    | 'field'
  +    | 'property'
  +    | 'receiver'
  +    | 'param'
  +    | 'setparam'
  +    | 'delegate'
  +    | 'file'
       | 'expect'
       | 'actual'
       | 'const'
  
positive.code: 
  singleAnnotation
      : annotationUseSiteTarget NL* unescapedAnnotation
      | '@' unescapedAnnotation
      ;
  
  multiAnnotation
      : annotationUseSiteTarget NL* '[' unescapedAnnotation+ ']'
      | '@' '[' unescapedAnnotation+ ']'
      ;
  
  annotationUseSiteTarget
      : '@' ('field' | 'property' | 'get' | 'set' | 'receiver' | 'param' | 'setparam' | 'delegate') NL* ':'
      ;
  
  unescapedAnnotation
  
negative.code:     ;
  
  label
      : simpleIdentifier (AT_NO_WS | AT_POST_WS) NL*
      ;
  
  controlStructureBody
  