IsUnknown.md

typelab / assertions / IsUnknown

type IsUnknown<T> = IsAny<T> extends true ? false : [unknown] extends [T] ? true : false;

Checks if a given type T is an unknown type.

Type Parameters

Type Parameter	Description
T	The type to be checked.

Returns

true if T is an unknown type, false otherwise.

Example

type Valid = IsUnknown<unknown>; // true
type Invalid = IsUnknown<string>; // false