Tiny 200b functional event emitter / pubsub.
"*"
event type listens to all eventsthis
Mitt was made for the browser, but works in any JavaScript runtime. It has no dependencies and supports IE9+.
This project uses node and npm. Go check them out if you don't have them locally installed.
$ npm install --save mitt
Then with a module bundler like rollup or webpack, use as you would anything else:
// using ES6 modules
import mitt from 'mitt'
// using CommonJS modules
var mitt = require('mitt')
The UMD build is also available on unpkg:
<script src="https://unpkg.com/mitt/dist/mitt.umd.js"></script>
You can find the library on window.mitt
.
import mitt from 'mitt'
const emitter = mitt()
// listen to an event
emitter.on('foo', e => console.log('foo', e) )
// listen to all events
emitter.on('*', (type, e) => console.log(type, e) )
// fire an event
emitter.emit('foo', { a: 'b' })
// working with handler references:
function onFoo() {}
emitter.on('foo', onFoo) // listen
emitter.off('foo', onFoo) // unlisten
import mitt from 'mitt';
const emitter: mitt.Emitter = mitt();
Mitt: Tiny (~200b) functional event emitter / pubsub.
Parameters
all
EventHandlerMapReturns Mitt
Register an event handler for the given type.
Parameters
type
String Type of event to listen for, or "*"
for all eventshandler
Function Function to call in response to given eventRemove an event handler for the given type.
Parameters
type
String Type of event to unregister handler
from, or "*"
handler
Function Handler function to removeInvoke all handlers for the given type.
If present, "*"
handlers are invoked after type-matched handlers.
Parameters
type
String The event type to invokeevt
Any? Any value (object is recommended and powerful), passed to each handlerFirst off, thanks for taking the time to contribute! Now, take a moment to be sure your contributions make sense to everyone else.
Development Start:
This project is typed with Flow Type annotations. To ensure you have the proper typings for this project run
flow-typed install
Found a problem? Want a new feature? First of all see if your issue or idea has already been reported. If don't, just open a new clear and descriptive issue.
Pull requests are the greatest contributions, so be sure they are focused in scope, and do avoid unrelated commits.
git clone https://github.com/<your-username>/mitt
cd mitt
git checkout -b my-new-feature
npm install
git commit -am 'Add some feature'
git push origin my-new-feature