@js-utilities/typecheck

Utility library for javascript type checking.

Usage no npm install needed!

<script type="module">
  import jsUtilitiesTypecheck from 'https://cdn.skypack.dev/@js-utilities/typecheck';
</script>

README

Type checking library

npm version Build Status

A set of super-simple type checkers. Each checker returns boolean value. Most checkers are typescript type predicates.

Installation

npm i -S @js-utilities/typecheck

Usage example

import { isCallable } from "@js-utilities/typecheck";

const a: unknown = global.value;

if (isCallable(a)) a();

Available checkers:

Checker Return type
isCallable boolean
isFunction value is Function
isArrowFunction boolean
isArray<T> value is T[]
isObject<T> value is T
isBoolean value is boolean
isUndefined value is undefined
isNumber value is number
isString value is string
isSymbol value is symbol
isNull value is null
isMap<T, U> value is Map<T, U>
isSet<T> value is Set<T>
isWeakSet<T> value is WeakSet<T>
isWeakMap<T, U> value is WeakMap<T, U>
isPromise<T> value is Promise<T>

License

MIT License