grammar/src/annotations.grm

/**
## Annotations
*/

annotations
  : (annotation | annotationList)*
  ;

annotation
  : "@" (annotationUseSiteTarget ":")? unescapedAnnotation
  ;

annotationList
  : "@" (annotationUseSiteTarget ":")? "[" unescapedAnnotation+ "]"
  ;

annotationUseSiteTarget
  : "field"
  : "file"
  : "property"
  : "get"
  : "set"
  : "receiver"
  : "param"
  : "setparam"
  : "delegate"
  ;

unescapedAnnotation
  : SimpleName{"."} typeArguments? valueArguments?
  ;