regex static method

FormFieldValidator regex(
  1. RegExp reg,
  2. String message
) 
 Validatorless.regex(RegExp(r'^[a-zA-Z]+$'), 'only letters')

Implementation

static FormFieldValidator regex(RegExp reg, String message) {
  return (v) {
    if (reg.hasMatch(v)) return null;
    return message;
  };
}