Class EventEmitter

A advanced EventEmitter which allows to declare event as natural function in the inheriting children class, function must start by on prefix to be recognized as an event. The function can define a behavior by default, and user can choose to redefine this behavior, or add an additionnal subscription for this event. In addition you can unsubscribe to multiple events with an AbortController

Example

class Logger extends EventEmitter {
   onLog(log:string) { console.log(log); } // behavior by default

   test() {
      // raise event onLog
      this.onLog('test');
   }
}

const logger = new Logger();
logger.test(); // displays a log 'test'

// redefine default behavior to display nothing
logger.onLog = () => {}
logger.test(); // displays nothing

// add an additionnal subscription
logger.on('log', console.log);
logger.test(); // displays a log 'test'

// remove the additionnal subscription
logger.off('log', console.log);
logger.test(); // displays nothing

// add two additionnal subscriptions with a AbortController
const controller = new AbortController();
logger.on('log', log => console.log(log), controller);
logger.on('log', log => console.error(log), controller);
logger.test(); // displays a log 'test' + an error 'test'

// Unsubscribe all the subscription with the AbortController
controller.abort();
logger.test(); // displays nothing
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