FunctionKeys

Since 1.0.0

Get keys of function properties.

Signature

type FunctionKeys<T> = {
  [K in keyof T]: T[K] extends (...args: any[]) => any ? K : never
}[keyof T]

Parameters

Parameter	Description
T	The object type

Description

Extracts the keys of all function properties from an object type.

Examples

Basic Usage

import type { FunctionKeys } from 'uni-types'

interface User {
  name: string
  age: number
  onClick: () => void
  onChange: (value: string) => void
}

type FnKeys = FunctionKeys<User>
// 'onClick' | 'onChange'

No Functions

interface Data {
  name: string
  email: string
}

type NoFns = FunctionKeys<Data> // never

Related

• NonFunctionKeys - Get non-function property keys
• FunctionOnly - Extract function properties
• DataOnly - Extract non-function properties