notInFn method

FieldValidator<T, R> notInFn(
  1. ValueGetter<List<R>> values, [
  2. MessageCallBack<R>? message
])

check is the value is not in values

Implementation

FieldValidator<T, R> notInFn(ValueGetter<List<R>> values,
    [MessageCallBack<R>? message]) {
  return next((messages, value) {
    var val = values();
    if (val.contains(value)) {
      return message?.call(messages, value) ?? messages.isNotIn(val);
    }
    return null;
  });
}