IfArray.md

typelab / conditions / IfArray

type IfArray<T, Then, Else> = _IfNotAnyOrNever<T, T extends ReadonlyArray ? Then : Else, Else>;

Resolves to Then if the type T is an array (readonly or writable), otherwise resolves to Else.

Type Parameters

Type Parameter	Default type	Description
T	‐	The type to be checked.
Then	‐	The type to return if T is an array.
Else	never	The type to return if T is not an array. Defaults to never.

Returns

Then if T is an array, Else otherwise.

Example

type Yes = IfArray<string[], 'yes', 'no'>; // 'yes'
type No = IfArray<string, 'yes', 'no'>; // 'no'
type YesOrNo = IfArray<string[] | string, 'yes', 'no'>; // 'yes' | 'no'