helper

var (
	WriterAssertion = &gad.TypeAssertion{
		Handlers: map[string]gad.TypeAssertionHandler{
			"writer": func(v gad.Object) (ok bool) {
				return gad.WriterFrom(v) != nil
			},
		},
	}

	ReaderAssertion = &gad.TypeAssertion{
		Handlers: map[string]gad.TypeAssertionHandler{
			"reader": func(v gad.Object) (ok bool) {
				return gad.ReaderFrom(v) != nil
			},
		},
	}
)