@imhonglu/type-guard

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Introduction

- A library providing zero dependencies type guard utilities.
- Provides a chaining API inspired by Jest's matcher pattern.
- Built on Proxy to minimize overhead and ensure type safety.

!demo-1

Table of Contents

- Installation
- Usage
- API Reference

Installation

``bash
npm install @imhonglu/type-guard
`

Usage

Type guards created using the composeGuards function can be negated using the not key.

For detailed usage examples, please refer to the API Reference.

`ts
import { composeGuards } from '@imhonglu/type-guard';

// Composing type guards
const has = composeGuards({
length: (value: unknown): value is object & { length: number } =>
typeof value === "object" && value !== null && "length" in value,
});
// {
// length: [Function];
// not: {
// length: [Function];
// };
// }

let value: unknown[] | number | undefined;

if (has.length(value)) { ... } // value is unknown[]
if (has.not.length(value)) { ... } // value is number | undefined
``

API Reference

- composeGuards - compose type guards
- negateGuards - negate type guards
- negateGuard - negate single type guard