65 lines
2.0 KiB
JavaScript
65 lines
2.0 KiB
JavaScript
|
//
|
||
|
// An event handler can take an optional event argument
|
||
|
// and should not return a value
|
||
|
|
||
|
|
||
|
|
||
|
// An array of all currently registered event handlers for a type
|
||
|
|
||
|
|
||
|
// A map of event types and their corresponding event handlers.
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
/** Mitt: Tiny (~200b) functional event emitter / pubsub.
|
||
|
* @name mitt
|
||
|
* @returns {Mitt}
|
||
|
*/
|
||
|
function mitt(all ) {
|
||
|
all = all || Object.create(null);
|
||
|
|
||
|
return {
|
||
|
/**
|
||
|
* Register an event handler for the given type.
|
||
|
*
|
||
|
* @param {String} type Type of event to listen for, or `"*"` for all events
|
||
|
* @param {Function} handler Function to call in response to given event
|
||
|
* @memberOf mitt
|
||
|
*/
|
||
|
on: function on(type , handler ) {
|
||
|
(all[type] || (all[type] = [])).push(handler);
|
||
|
},
|
||
|
|
||
|
/**
|
||
|
* Remove an event handler for the given type.
|
||
|
*
|
||
|
* @param {String} type Type of event to unregister `handler` from, or `"*"`
|
||
|
* @param {Function} handler Handler function to remove
|
||
|
* @memberOf mitt
|
||
|
*/
|
||
|
off: function off(type , handler ) {
|
||
|
if (all[type]) {
|
||
|
all[type].splice(all[type].indexOf(handler) >>> 0, 1);
|
||
|
}
|
||
|
},
|
||
|
|
||
|
/**
|
||
|
* Invoke all handlers for the given type.
|
||
|
* If present, `"*"` handlers are invoked after type-matched handlers.
|
||
|
*
|
||
|
* @param {String} type The event type to invoke
|
||
|
* @param {Any} [evt] Any value (object is recommended and powerful), passed to each handler
|
||
|
* @memberOf mitt
|
||
|
*/
|
||
|
emit: function emit(type , evt ) {
|
||
|
(all[type] || []).slice().map(function (handler) { handler(evt); });
|
||
|
(all['*'] || []).slice().map(function (handler) { handler(type, evt); });
|
||
|
}
|
||
|
};
|
||
|
}
|
||
|
|
||
|
export default mitt;
|
||
|
//# sourceMappingURL=mitt.es.js.map
|