https://github.com/vitalishapovalov/typecheck

Super-simple type checkers
https://github.com/vitalishapovalov/typecheck

type-predicates typechecking typescript utilities-js utilities-library

Last synced: 2 months ago
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Super-simple type checkers

• Host: GitHub
• URL: https://github.com/vitalishapovalov/typecheck
• Owner: vitalishapovalov
• License: mit
• Created: 2019-10-24T18:01:07.000Z (about 6 years ago)
• Default Branch: master
• Last Pushed: 2023-03-05T11:48:37.000Z (almost 3 years ago)
• Last Synced: 2025-07-06T20:54:59.355Z (6 months ago)
• Topics: type-predicates, typechecking, typescript, utilities-js, utilities-library
• Language: TypeScript
• Size: 473 KB
• Stars: 3
• Watchers: 1
• Forks: 0
• Open Issues: 7
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

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README

          
# Type checking library

[![npm version](https://badge.fury.io/js/%40js-utilities%2Ftypecheck.svg)](https://badge.fury.io/js/%40js-utilities%2Ftypecheck)

[![Build Status](https://travis-ci.org/vitalishapovalov/Typecheck.svg?branch=master)](https://travis-ci.org/vitalishapovalov/Typecheck)

A set of super-simple type checkers. Each checker returns `boolean` value. Most checkers are typescript [type predicates](https://www.typescriptlang.org/docs/handbook/advanced-types.html#using-type-predicates).

## Installation

```bash

npm i -S @js-utilities/typecheck

```

## Usage example

```typescript

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`         | `value is T[]`                 |         

| `isObject`        | `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`        | `value is Map`           | 

| `isSet`           | `value is Set`              |     

| `isWeakSet`       | `value is WeakSet`          |         

| `isWeakMap`    | `value is WeakMap`       |    

| `isPromise`       | `value is Promise`          |    

    

## License

[MIT License](https://github.com/vitalishapovalov/Typecheck/blob/master/LICENSE)