WritableKeys

Since 1.0.0

Get writable property keys.

Signature

type WritableKeys<T> = {
  [K in keyof T]-?: IfEquals<
    { [Q in K]: T[K] },
    { -readonly [Q in K]: T[K] },
    K,
    never
  >
}[keyof T]

Parameters

Parameter	Description
T	The object type

Description

Extracts all writable (non-readonly) property keys from an object type.

Examples

Basic Usage

import type { WritableKeys } from 'uni-types'

interface User {
  id: number
  name: string
  readonly email: string
  readonly createdAt: Date
}

type Writable = WritableKeys<User>
// 'id' | 'name'

All Readonly

interface ReadonlyUser {
  readonly id: number
  readonly name: string
}

type NoWritable = WritableKeys<ReadonlyUser> // never

Related

• ReadonlyKeys - Get readonly property keys
• RequiredKeys - Get required property keys
• OptionalKeys - Get optional property keys