API reference › @evolu/common › Type › typed

Call Signature

function typed<Tag>(tag: Tag): TypedType<Tag>;

Defined in: packages/common/src/Type.ts:3528

Creates a runtime-validated typed object with a type discriminant.

Example

const Card = typed("Card", {
  cardNumber: CardNumber,
  expiry: DateIso,
});

const Cash = typed("Cash", {
  currency: NonEmptyTrimmedString,
});

const Payment = union(Card, Cash);
type Payment = typeof Payment.Type;

const result = Payment.fromUnknown(data);
if (result.ok) {
  switch (result.value.type) {
    case "Card":
      console.log(result.value.cardNumber);
      break;
    case "Cash":
      console.log(result.value.currency);
      break;
  }
}

See

Typed for type-only discrimination.

Call Signature

function typed<Tag, Props>(tag: Tag, props: Props): TypedType<Tag, Props>;

Defined in: packages/common/src/Type.ts:3530

With additional properties.

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