RequireFunction

Since 1.3.0

Ensure type is a function.

Signature

type RequireFunction<T> = T extends (...args: any[]) => any ? T : never

Parameters

Parameter	Description
T	The type to check

Examples

Basic Usage

import type { RequireFunction } from 'uni-types'

type Result = RequireFunction<() => void> // () => void
type Failed = RequireFunction<string> // never

With Typed Functions

type Handler = (event: Event) => void
type ValidHandler = RequireFunction<Handler> // Handler

With Union Types

type MaybeFunc = string | ((x: number) => number)
type OnlyFunc = RequireFunction<MaybeFunc> // (x: number) => number

Related

• RequireArray - Ensure type is an array
• RequireNotNullish - Ensure type is not null or undefined