How to use the listenerCount function from events

Find comprehensive JavaScript events.listenerCount code examples handpicked from public code repositorys.

events.listenerCount is a method in Node.js that returns the number of listeners subscribed to a particular event.

kurento-utils.js

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        return [stream];
    };
}
var iceCandidateFunction = function (event) {
    var candidate = event.candidate;
    if (EventEmitter.listenerCount(self, 'icecandidate') || EventEmitter.listenerCount(self, 'candidategatheringdone')) {
        if (candidate) {
            var cand;
            if (multistream && usePlanB) {
                cand = interop.candidateToUnifiedPlan(candidate);

+ 4 other calls in file

Sequence.js

GitHub: Hsinkai2000/OldEgg

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var Packets        = require('../packets');
var ErrorConstants = require('../constants/errors');
var Timer          = require('../Timer');


// istanbul ignore next: Node.js < 0.10 not covered
var listenerCount = EventEmitter.listenerCount
  || function(emitter, type){ return emitter.listeners(type).length; };


var LONG_STACK_DELIMITER = '\n    --------------------\n';

How does events.listenerCount work?

events.listenerCount is a built-in method in the Node.js events module that can be used to determine the number of listeners subscribed to a specific event. The method takes two arguments: the first argument is the EventEmitter object, which is used to emit and handle events in Node.js, and the second argument is the name of the event for which you want to count the listeners. Once these arguments are passed to events.listenerCount, the method returns an integer indicating the number of listeners currently subscribed to the specified event. If the specified event has no listeners, events.listenerCount returns 0. If the EventEmitter object or the event name argument is null or undefined, the method will throw an error. events.listenerCount can be useful when you need to know how many listeners are currently subscribed to an event, for example to debug issues related to event handling or to optimize performance by reducing the number of listeners.

pouchdb-browser-7.2.2.js

GitHub: sam-echoapps/JobPlus

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  return false;
}


function listenerCount(ee, type) {
  return 'listenerCount' in ee ? ee.listenerCount(type) :
                                 EE.listenerCount(ee, type);
}


function parseDesignDocFunctionName(s) {
  if (!s) {

server.js

GitHub: musmanamjad1/AI_GPT_React

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this._invokeDefault(socket)

// For v0.8, 0.10 and 0.12
if (process.versions.modules < 46) {
  // eslint-disable-next-line
  this.listenerCount = EventEmitter.listenerCount.bind(this)
}

// Add lazy `checkContinue` listener, otherwise `res.writeContinue` will be
// called before the response object was patched by us.

Ai Example

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const EventEmitter = require("events");

// Create a new EventEmitter object
const myEmitter = new EventEmitter();

// Add some listeners to the 'myEvent' event
myEmitter.on("myEvent", () => {
  console.log("Listener 1");
});

myEmitter.on("myEvent", () => {
  console.log("Listener 2");
});

// Count the number of listeners for the 'myEvent' event
const numListeners = EventEmitter.listenerCount(myEmitter, "myEvent");

console.log(`Number of listeners: ${numListeners}`); // Output: Number of listeners: 2

In this example, we create a new EventEmitter object called myEmitter. We then add two event listeners to the myEvent event using the on method. Afterward, we use the EventEmitter.listenerCount method to count the number of listeners currently subscribed to the myEvent event, and we store the result in a variable called numListeners. Finally, we use console.log to output the value of numListeners to the console, which will be 2 in this case, indicating that two listeners are currently subscribed to the myEvent event.

object_hash_test.js

GitHub: musmanamjad1/AI_GPT_React

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}

// if the dest has an error, then stop piping into it.
// however, don't suppress the throwing behavior for this.
// check for listeners before emit removes one-time listeners.
var errListeners = EE.listenerCount(dest, 'error');
function onerror(er) {
  unpipe();
  if (errListeners === 0 && EE.listenerCount(dest, 'error') === 0)
    dest.emit('error', er);

directory-reader.js

GitHub: musmanamjad1/AI_GPT_React

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let needStats =
  !maxDepthReached ||                                 // we need the fs.Stats to know if it's a directory
  options.stats ||                                    // the user wants fs.Stats objects returned
  options.recurseFn ||                                // we need fs.Stats for the recurse function
  options.filterFn ||                                 // we need fs.Stats for the filter function
  EventEmitter.listenerCount(stream, 'file') ||       // we need the fs.Stats to know if it's a file
  EventEmitter.listenerCount(stream, 'directory') ||  // we need the fs.Stats to know if it's a directory
  EventEmitter.listenerCount(stream, 'symlink');      // we need the fs.Stats to know if it's a symlink

// If we don't need stats, then exit early

+ 2 other calls in file

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