evt/README.md

Type safe replacement for node's EventEmitter

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    💧<i>EventEmitter's typesafe replacement</i>💧
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  <a href="https://www.evt.land">Home</a>
  -
  <a href="https://docs.evt.land">Documentation</a>
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---

`'evt'` is intended to be a replacement for `'events'`.  
It makes heavy use of **typescript**'s type inference features to provide **type safety** while keeping things **concise and elegant** 🍸.

<b>Suitable for any JS runtime env (deno, node, old browsers, react-native ...)</b>
- ✅ It is both a [Deno](https://deno.land/x/evt) and an [NPM](https://www.npmjs.com/evt) module. ( Achieved with [Denoify](https://github.com/garronej/denoify) ) 
- ✅ No external dependencies ([`tsafe`](https://github.com/garronej/tsafe), [`run-exclusive`](https://github.com/garronej/run_exclusive) and [`minimal-polyfills`](https://github.com/garronej/minimal_polyfills) are all from the same author as EVT).
- ✅ [Makes it easy to work with events in React](https://docs.evt.land/react-hooks).  

Can be imported in TypeScript projects using version TypeScript >= 3.8 (February 20th, 2020) and in any plain JS projects.

> NOTE: There is very few breaking changes from v1 to v2. [Check them out](https://docs.evt.land/v1-greater-than-v2).  

# Who is using it

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    <a href="https://connext.network">
        <img src="https://user-images.githubusercontent.com/6702424/84102640-4e1e5c80-aa11-11ea-9d13-df0a65c8cdaf.png">
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    <a href="https://www.semasim.com">
        <img src="https://user-images.githubusercontent.com/6702424/84102785-aead9980-aa11-11ea-915b-5c4a5282c44e.png"> 
    </a>
    <br>
    <a href="https://thegraph.com">
        <img src="https://user-images.githubusercontent.com/6702424/179356567-19e2ca0a-9797-4c82-8a45-7e1d0de896a9.png"> 
    </a>
    <a href="https://insee.fr">
        <img src="https://user-images.githubusercontent.com/6702424/117936881-a9358f00-b305-11eb-84b9-e61593632bdd.png"> 
    </a>
    <a href="https://www.etalab.gouv.fr/">
        <img src="https://user-images.githubusercontent.com/6702424/179345089-3aee6170-e7aa-4b38-adf1-f7d132aa7be4.png"> 
    </a>
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# Install / Import

## In Deno:
```typescript
import { Evt } from "https://deno.land/x/evt/mod.ts";
```
## Anywhere else:
```bash
$ npm install --save evt
```
```typescript
import { Evt } from "evt"; 
```

# Try it

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    <img src="https://user-images.githubusercontent.com/6702424/179363007-582acf54-8f83-42ac-a062-562f8de40d14.gif">  
    <a href="https://stackblitz.com/edit/evt-playground-gfnidx?file=index.ts">Playground</a>
</p>

# Motivations

There are a lot of things that can't easily be done with `EventEmitter`:

* Enforcing **type safety**.
* Removing a particular listener ( if the callback is an anonymous function ).
* Adding a one-time listener for the next event that meets a condition.
* Waiting \(via a Promise\) for one thing or another to happen.  
_Example: waiting at most one second for the next message, stop waiting if the socket disconnects._

Why would someone pick EVT over RxJS:  

* EVT's learning curve is not as steep as RxJS's. 
* Generates code that is easier to grasp for people not familiar with reactive programming.

EVT is an attempt to address all these points while trying to remain as accessible as `EventEmitter`.  
  
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  <a href="https://evt.land">Get Started</a>
</p>

# The sticker

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    <a href="https://teespring.com/fr/evt-sticker">Shop</a>
</p>