# EventReplayEmitter

An extension to Node's EventEmitter that supports event replay. In other words,
if a listener is added using either `addListenerWithReplay` or `onWithReplay`,
then it will instantly trigger the listener with previous event data (if no data
was previously emitted, then the listener will not get triggered on 
registration).

## Usage Examples

In order to get event replay on listener registration, simply utilize the
`addListenerWithReplay` method like so:

```js
import { ReplayEventEmitter } from "replay-event-emitter";

// Instantiate the event emitter
const eventEmitter = new ReplayEventEmitter();

// Emit an event before adding a listener
eventEmitter.emit("exampleEvent", "someData");

// Subscribe using addListenerWithReplay
eventEmitter.addListenerWithReplay("exampleEvent", (data) => {
  // This handler will get triggered despite the data emission happening BEFORE
  // the event registration.
  console.log(data);
});
```

You could also use the shorthand method `onWithRepeat`, like so:

```js
eventEmitter.onWithReplay("exampleEvent", (data) => {
  console.log(data);
});
```

All the original functionality of the EventEmitter is still intact:

```js
import { ReplayEventEmitter } from "replay-event-emitter";

const eventEmitter = new ReplayEventEmitter();

eventEmitter.emit("exampleEvent", "someData");

eventEmitter.addListener("exampleEvent", (data) => {
  // This handler will NOT get triggered, as this is not a replay method and the
  // data emission happened BEFORE the event registration.
  console.log(data);
});
```