Function createParser

packages/forms/signals/src/util/parser.ts:41–68

(
  getValue: () => TValue,
  setValue: (value: TValue) => void,
  parse: (raw: TRaw) => ParseResult<TValue>,
)

 * @returns A {@link Parser} instance.
 */
export function createParser<TValue, TRaw>(
  getValue: () => TValue,
  setValue: (value: TValue) => void,
  parse: (raw: TRaw) => ParseResult<TValue>,
): Parser<TRaw> {
  const errors = linkedSignal({
    source: getValue,
    computation: () => [] as readonly ValidationError.WithoutFieldTree[],
    equal: shallowArrayEquals,
  });

  const setRawValue = (rawValue: TRaw) => {
    const result = parse(rawValue);
    errors.set(normalizeErrors(result.error));
    if (result.value !== undefined) {
      setValue(result.value);
    }
    // `errors` is a linked signal sourced from the model value; write parse errors after
    // model updates so `{value, errors}` results do not get reset by the recomputation.
    errors.set(normalizeErrors(result.error));
  };

  const reset = () => {
    errors.set([]);
  };

  return {errors: errors.asReadonly(), setRawValue, reset};
}