oneOf method

JarMixed oneOf(
  1. List<T> allowed, [
  2. String? message
])

Implementation

JarMixed oneOf(List<T> allowed, [String? message]) {
  return addValidator((value) {
    if (value == null) return null;
    return allowed.contains(value)
        ? null
        : (message ?? 'Value must be one of: ${allowed.join(", ")}');
  });
}