pattern static method

PrismValidator pattern(
  1. RegExp pattern, [
  2. String? message
])

Fails when the value does not match pattern.

Implementation

static PrismValidator pattern(RegExp pattern, [String? message]) => (value) {
  final v = value ?? '';
  if (v.isEmpty) return null; // let `required` handle emptiness
  return pattern.hasMatch(v) ? null : (message ?? 'Invalid format');
};