@t8/event-patterns/README.md

Lightweight event emitter with flexible event type matching

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# @t8/event-patterns

*Lightweight zero-dependency event emitter with flexible event type matching*

Installation: `npm i @t8/event-patterns`

## Usage

Initialization:

```js
import {EventEmitter} from '@t8/event-patterns';

let eventEmitter = new EventEmitter();
```

Adding a handler of a specific event type:

```js
eventEmitter.on('task started', event => {
    console.log(event);
});
```

Of all events matching the pattern:

```js
eventEmitter.on(/^task\s/, event => {
    console.log(event);
});
```

With captured parameters:

```js
eventEmitter.on(/^(\S+)\s(?<status>.*)$/, event => {
    console.log(event.params[0], event.params.status);
});
```

Adding a handler of all events dispatched to the `eventEmitter` instance:

```js
let listener = eventEmitter.on('*', event => {
    console.log(event);
});
```

Dispatching an event of a specific type and properties:

```js
eventEmitter.emit('task started', {x: 42});
```

Removing a previously declared listener:

```js
listener.remove();
```