/// <summary> /// For a simple yes/no question where 'y' is true /// </summary> public static Validator <bool> Bool() { return(response => Regex.IsMatch(response, "^(y|n|yes|no)$", RegexOptions.IgnoreCase) ? Validated <bool> .Success(response.StartsWith("y", StringComparison.OrdinalIgnoreCase)) : Validated <bool> .Error("Please enter 'y' or 'n'.")); }