API reference / @evolu/common / Type / nullishOr

Function: nullishOr()

function nullishOr<T>(
  type,
): UnionType<
  [
    Type<
      "Undefined",
      undefined,
      undefined,
      UndefinedError,
      undefined,
      UndefinedError
    >,
    Type<"Null", null, null, NullError, null, NullError>,
    T,
  ]
>;

Defined in: packages/common/src/Type.ts:3217

union(undefined, null, T) Type.

Learn more: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html#nullish-coalescing

Example

const NullishOrString = nullishOr(String);
NullishOrString.from("test"); // ok("test")
NullishOrString.from(null); // ok(null)
NullishOrString.from(undefined); // ok()
NullishOrString.from(42); // err(...)

Type Parameters

Type Parameter
`T` extends `AnyType`

Parameters

Parameter	Type
`type`	`T`

Returns

UnionType<[Type<"Undefined", undefined, undefined, UndefinedError, undefined, UndefinedError>, Type<"Null", null, null, NullError, null, NullError>, T]>