return i.appendConstraint(func() error {
		typeOf := reflect.TypeOf(expected)
		protoMessageType := reflect.TypeOf((*proto.Message)(nil)).Elem()
		if typeOf.Implements(protoMessageType) {
			return i.equalsStruct(expected.(proto.Message), path)
		}
		switch kind := typeOf.Kind(); kind {
		case reflect.String:
			return i.equalsString(reflect.ValueOf(expected).String(), path)
		case reflect.Bool: