ListIncludes

Since 1.3.0

Check if a type-level list (tuple) includes a specific element. Returns true if the element is found, otherwise false.

Signature

export type ListIncludes<T extends readonly unknown[], U> = T extends [infer First, ...infer Rest]
  ? First extends U
    ? true
    : ListIncludes<Rest, U>
  : false

Parameters

Parameter	Description
T	The tuple to search in
U	The element type to check for

Examples

Basic Usage

import type { ListIncludes } from 'uni-types'

type Result = ListIncludes<[1, 2, 3], 2>
// true

Element Not Found

type Result = ListIncludes<[1, 2, 3], 4>
// false