https://github.com/abraham/reflection

Lightweight (3K) ES Module implementation of reflect-metadata
https://github.com/abraham/reflection

decorators hacktoberfest javascript metadata reflect-metadata typescript

Last synced: 23 days ago
JSON representation

Lightweight (3K) ES Module implementation of reflect-metadata

• Host: GitHub
• URL: https://github.com/abraham/reflection
• Owner: abraham
• License: mit
• Created: 2018-07-23T16:00:38.000Z (almost 7 years ago)
• Default Branch: main
• Last Pushed: 2025-03-08T21:43:23.000Z (3 months ago)
• Last Synced: 2025-05-08T15:50:21.699Z (29 days ago)
• Topics: decorators, hacktoberfest, javascript, metadata, reflect-metadata, typescript
• Language: TypeScript
• Homepage: https://www.npmjs.com/package/@abraham/reflection
• Size: 490 KB
• Stars: 275
• Watchers: 6
• Forks: 16
• Open Issues: 2
• Metadata Files:
  • Readme: README.md
  • License: LICENSE.md

Awesome Lists containing this project

README

        
[![Version Status](https://img.shields.io/npm/v/@abraham/reflection.svg?style=flat&label=version&colorB=4bc524)](https://npmjs.com/package/@abraham/reflection)

[![Build Status](https://github.com/abraham/reflection/workflows/Index/badge.svg)](https://github.com/abraham/reflection/actions)

[![npm bundle size (minified + gzip)](https://img.shields.io/bundlephobia/minzip/@abraham/reflection.svg?style=flat&colorB=4bc524)](https://bundlephobia.com/result?p=@abraham/reflection)

[![Coverage Status](https://coveralls.io/repos/github/abraham/reflection/badge.svg?branch=master)](https://coveralls.io/github/abraham/reflection?branch=master)

# Reflection

Lightweight ES Module implementation of [reflect-metadata](https://github.com/rbuckton/reflect-metadata/) to work with TypeScript's [experimental decorator support](https://www.typescriptlang.org/docs/handbook/decorators.html).

## Why?

The main reason for this library is to provide a much smaller implementation that can be included as a module.

- ES module

  - `reflection` can be loaded with ``

- Size (uncompressed)

  - [`reflect-metadata`](https://github.com/rbuckton/reflect-metadata) is ~50K

  - [`core-js/es7/reflect`](https://github.com/zloirock/core-js) is ~80K

  - `@abraham/reflection` is ~3K

Read about how to [drop 20K from your production Angular app](https://bendyworks.com/blog/drop-20k-from-your-production-angular-app) by switching to this.

## Install

```sh

npm install @abraham/reflection

```

## Usage

```ts

import '@abraham/reflection';

Reflect.defineMetadata(metadataKey, metadataValue, target);

```

You can also import `Reflection`:

```ts

import { Reflection as Reflect } from '@abraham/reflection';

Reflect.defineMetadata(metadataKey, metadataValue, target);

```

## API

Reflection does not currently cover the complete API surface of reflect-metadata. The following methods are available:

```ts

Reflect.decorate(...);

Reflect.defineMetadata(...);

Reflect.getMetadata(...);

Reflect.hasMetadata(...);

Reflect.getOwnMetadata(...);

Reflect.hasOwnMetadata(...);

Reflect.metadata(...);

```