type-guarden 🌱

Collection of type guards for TypeScript.

Installation

npm install type-guarden

Usage

import { isKeyOf, isElementOf } from 'type-guarden'

const obj = {
  foo: 'bar',
  baz: 42,
}

const arr = ['foo', 'bar', 'baz']

let key: unknown
let element: unknown

if (isKeyOf(obj, key)) {
  // `key` is 'foo' | 'baz'
}

if (isElementOf(arr, element)) {
  // `element` is 'foo' | 'bar' | 'baz'
}

APIs

• isKeyOf
• isElementOf
• isBigInt
• isBoolean
• isNull
• isNumber
• isString
• isSymbol
• isUndefined
• isFunction
• isObject
• isPlainObject
• isPromise
• isPrimitive
• isTruthy
• isFalsy