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id	title	sidebar_label	sidebar_position	custom_edit_url
SernEmitter	Class: SernEmitter	SernEmitter	0	null

Since

1.0.0

Hierarchy

EventEmitter

↳ SernEmitter

Constructors

constructor

• new SernEmitter(): SernEmitter

Returns

SernEmitter

Overrides

EventEmitter.constructor

Defined in

src/core/structures/sern-emitter.ts:10

Properties

captureRejectionSymbol

▪ Static Readonly captureRejectionSymbol: typeof captureRejectionSymbol

Inherited from

EventEmitter.captureRejectionSymbol

Defined in

node_modules/@types/node/events.d.ts:357

captureRejections

▪ Static captureRejections: boolean

Sets or gets the default captureRejection value for all emitters.

Inherited from

EventEmitter.captureRejections

Defined in

node_modules/@types/node/events.d.ts:362

defaultMaxListeners

▪ Static defaultMaxListeners: number

Inherited from

EventEmitter.defaultMaxListeners

Defined in

node_modules/@types/node/events.d.ts:363

errorMonitor

▪ Static Readonly errorMonitor: typeof errorMonitor

This symbol shall be used to install a listener for only monitoring 'error' events. Listeners installed using this symbol are called before the regular 'error' listeners are called.

Installing a listener using this symbol does not change the behavior once an 'error' event is emitted, therefore the process will still crash if no regular 'error' listener is installed.

Inherited from

EventEmitter.errorMonitor

Defined in

node_modules/@types/node/events.d.ts:356

Methods

addListener

▸ addListener(eventName, listener): SernEmitter

Alias for emitter.on(eventName, listener).

Parameters

Name	Type
`eventName`	`string` \| `symbol`
`listener`	(...`args`: `any`[]) => `void`

Returns

SernEmitter

Since

v0.1.26

Inherited from

EventEmitter.addListener

Defined in

node_modules/@types/node/events.d.ts:383

emit

▸ emit<T>(eventName, ...args): boolean

Listening to sern events with on. This event stays on until a crash or a normal exit

Type parameters

Name	Type
`T`	extends keyof `SernEventsMapping`

Parameters

Name	Type	Description
`eventName`	`T`
`...args`	`SernEventsMapping`[`T`]	the arguments for emitting the eventName

Returns

boolean

Overrides

EventEmitter.emit

Defined in

src/core/structures/sern-emitter.ts:40

eventNames

▸ eventNames(): (string | symbol)[]

Returns an array listing the events for which the emitter has registered listeners. The values in the array are strings or Symbols.

const EventEmitter = require('events');
const myEE = new EventEmitter();
myEE.on('foo', () => {});
myEE.on('bar', () => {});

const sym = Symbol('symbol');
myEE.on(sym, () => {});

console.log(myEE.eventNames());
// Prints: [ 'foo', 'bar', Symbol(symbol) ]

Returns

(string | symbol)[]

Since

v6.0.0

Inherited from

EventEmitter.eventNames

Defined in

node_modules/@types/node/events.d.ts:702

getMaxListeners

▸ getMaxListeners(): number

Returns the current max listener value for the EventEmitter which is either set by emitter.setMaxListeners(n) or defaults to defaultMaxListeners.

Returns

number

Since

v1.0.0

Inherited from

EventEmitter.getMaxListeners

Defined in

node_modules/@types/node/events.d.ts:555

listenerCount

▸ listenerCount(eventName, listener?): number

Returns the number of listeners listening to the event named eventName.

If listener is provided, it will return how many times the listener is found in the list of the listeners of the event.

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event being listened for
`listener?`	`Function`	The event handler function

Returns

number

Since

v3.2.0

Inherited from

EventEmitter.listenerCount

Defined in

node_modules/@types/node/events.d.ts:649

listeners

▸ listeners(eventName): Function[]

Returns a copy of the array of listeners for the event named eventName.

server.on('connection', (stream) => {
  console.log('someone connected!');
});
console.log(util.inspect(server.listeners('connection')));
// Prints: [ [Function] ]

Parameters

Name	Type
`eventName`	`string` \| `symbol`

Returns

Function[]

Since

v0.1.26

Inherited from

EventEmitter.listeners

Defined in

node_modules/@types/node/events.d.ts:568

off

▸ off(eventName, listener): SernEmitter

Alias for emitter.removeListener().

Parameters

Name	Type
`eventName`	`string` \| `symbol`
`listener`	(...`args`: `any`[]) => `void`

Returns

SernEmitter

Since

v10.0.0

Inherited from

EventEmitter.off

Defined in

node_modules/@types/node/events.d.ts:528

on

▸ on<T>(eventName, listener): SernEmitter

Listening to sern events with on. This event stays on until a crash or a normal exit

Type parameters

Name	Type
`T`	extends keyof `SernEventsMapping`

Parameters

Name	Type	Description
`eventName`	`T`
`listener`	(...`args`: `SernEventsMapping`[`T`][]) => `void`	what to do with the data

Returns

SernEmitter

Overrides

EventEmitter.on

Defined in

src/core/structures/sern-emitter.ts:18

once

▸ once<T>(eventName, listener): SernEmitter

Listening to sern events with on. This event stays on until a crash or a normal exit

Type parameters

Name	Type
`T`	extends keyof `SernEventsMapping`

Parameters

Name	Type	Description
`eventName`	`T`
`listener`	(...`args`: `SernEventsMapping`[`T`][]) => `void`	what to do with the data

Returns

SernEmitter

Overrides

EventEmitter.once

Defined in

src/core/structures/sern-emitter.ts:29

prependListener

▸ prependListener(eventName, listener): SernEmitter

Adds the listener function to the beginning of the listeners array for the event named eventName. No checks are made to see if the listener has already been added. Multiple calls passing the same combination of eventNameand listener will result in the listener being added, and called, multiple times.

server.prependListener('connection', (stream) => {
  console.log('someone connected!');
});

Returns a reference to the EventEmitter, so that calls can be chained.

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event.
`listener`	(...`args`: `any`[]) => `void`	The callback function

Returns

SernEmitter

Since

v6.0.0

Inherited from

EventEmitter.prependListener

Defined in

node_modules/@types/node/events.d.ts:667

prependOnceListener

▸ prependOnceListener(eventName, listener): SernEmitter

Adds a one-timelistener function for the event named eventName to the beginning of the listeners array. The next time eventName is triggered, this listener is removed, and then invoked.

server.prependOnceListener('connection', (stream) => {
  console.log('Ah, we have our first user!');
});

Returns a reference to the EventEmitter, so that calls can be chained.

Parameters

Name	Type	Description
`eventName`	`string` \| `symbol`	The name of the event.
`listener`	(...`args`: `any`[]) => `void`	The callback function

Returns

SernEmitter

Since

v6.0.0

Inherited from

EventEmitter.prependOnceListener

Defined in

node_modules/@types/node/events.d.ts:683

rawListeners

▸ rawListeners(eventName): Function[]

Returns a copy of the array of listeners for the event named eventName, including any wrappers (such as those created by .once()).

const emitter = new EventEmitter();
emitter.once('log', () => console.log('log once'));

// Returns a new Array with a function `onceWrapper` which has a property
// `listener` which contains the original listener bound above
const listeners = emitter.rawListeners('log');
const logFnWrapper = listeners[0];

// Logs "log once" to the console and does not unbind the `once` event
logFnWrapper.listener();

// Logs "log once" to the console and removes the listener
logFnWrapper();

emitter.on('log', () => console.log('log persistently'));
// Will return a new Array with a single function bound by `.on()` above
const newListeners = emitter.rawListeners('log');

// Logs "log persistently" twice
newListeners[0]();
emitter.emit('log');

Parameters

Name	Type
`eventName`	`string` \| `symbol`

Returns

Function[]

Since

v9.4.0

Inherited from

EventEmitter.rawListeners

Defined in

node_modules/@types/node/events.d.ts:598

removeAllListeners

▸ removeAllListeners(event?): SernEmitter

Removes all listeners, or those of the specified eventName.

It is bad practice to remove listeners added elsewhere in the code, particularly when the EventEmitter instance was created by some other component or module (e.g. sockets or file streams).

Returns a reference to the EventEmitter, so that calls can be chained.

Parameters

Name	Type
`event?`	`string` \| `symbol`

Returns

SernEmitter

Since

v0.1.26

Inherited from

EventEmitter.removeAllListeners

Defined in

node_modules/@types/node/events.d.ts:539

removeListener

▸ removeListener(eventName, listener): SernEmitter

Removes the specified listener from the listener array for the event namedeventName.

const callback = (stream) => {
  console.log('someone connected!');
};
server.on('connection', callback);
// ...
server.removeListener('connection', callback);

removeListener() will remove, at most, one instance of a listener from the listener array. If any single listener has been added multiple times to the listener array for the specified eventName, then removeListener() must be called multiple times to remove each instance.

Once an event is emitted, all listeners attached to it at the time of emitting are called in order. This implies that anyremoveListener() or removeAllListeners() calls after emitting and before the last listener finishes execution will not remove them fromemit() in progress. Subsequent events behave as expected.

const myEmitter = new MyEmitter();

const callbackA = () => {
  console.log('A');
  myEmitter.removeListener('event', callbackB);
};

const callbackB = () => {
  console.log('B');
};

myEmitter.on('event', callbackA);

myEmitter.on('event', callbackB);

// callbackA removes listener callbackB but it will still be called.
// Internal listener array at time of emit [callbackA, callbackB]
myEmitter.emit('event');
// Prints:
//   A
//   B

// callbackB is now removed.
// Internal listener array [callbackA]
myEmitter.emit('event');
// Prints:
//   A

Because listeners are managed using an internal array, calling this will change the position indices of any listener registered after the listener being removed. This will not impact the order in which listeners are called, but it means that any copies of the listener array as returned by the emitter.listeners() method will need to be recreated.

When a single function has been added as a handler multiple times for a single event (as in the example below), removeListener() will remove the most recently added instance. In the example the once('ping')listener is removed:

const ee = new EventEmitter();

function pong() {
  console.log('pong');
}

ee.on('ping', pong);
ee.once('ping', pong);
ee.removeListener('ping', pong);

ee.emit('ping');
ee.emit('ping');

Returns a reference to the EventEmitter, so that calls can be chained.

Parameters

Name	Type
`eventName`	`string` \| `symbol`
`listener`	(...`args`: `any`[]) => `void`

Returns

SernEmitter

Since

v0.1.26

Inherited from

EventEmitter.removeListener

Defined in

node_modules/@types/node/events.d.ts:523

setMaxListeners

▸ setMaxListeners(n): SernEmitter

By default EventEmitters will print a warning if more than 10 listeners are added for a particular event. This is a useful default that helps finding memory leaks. The emitter.setMaxListeners() method allows the limit to be modified for this specific EventEmitter instance. The value can be set toInfinity (or 0) to indicate an unlimited number of listeners.

Returns a reference to the EventEmitter, so that calls can be chained.

Parameters

Name	Type
`n`	`number`

Returns

SernEmitter

Since

v0.3.5

Inherited from

EventEmitter.setMaxListeners

Defined in

node_modules/@types/node/events.d.ts:549

failure

▸ failure(module?, reason?): Object

Creates a compliant SernEmitter failure payload

Parameters

Name	Type
`module?`	`Module`
`reason?`	`unknown`

Returns

Object

Name	Type
`module?`	`AnyModule`
`reason`	`string` \| `Error`
`type`	`Failure`

Defined in

src/core/structures/sern-emitter.ts:59

getEventListeners

▸ getEventListeners(emitter, name): Function[]

Returns a copy of the array of listeners for the event named eventName.

For EventEmitters this behaves exactly the same as calling .listeners on the emitter.

For EventTargets this is the only way to get the event listeners for the event target. This is useful for debugging and diagnostic purposes.

const { getEventListeners, EventEmitter } = require('events');

{
  const ee = new EventEmitter();
  const listener = () => console.log('Events are fun');
  ee.on('foo', listener);
  getEventListeners(ee, 'foo'); // [listener]
}
{
  const et = new EventTarget();
  const listener = () => console.log('Events are fun');
  et.addEventListener('foo', listener);
  getEventListeners(et, 'foo'); // [listener]
}

Parameters

Name	Type
`emitter`	`EventEmitter` \| `_DOMEventTarget`
`name`	`string` \| `symbol`

Returns

Function[]

Since

v15.2.0, v14.17.0

Inherited from

EventEmitter.getEventListeners

Defined in

node_modules/@types/node/events.d.ts:299

getMaxListeners

▸ getMaxListeners(emitter): number

Returns the currently set max amount of listeners.

For EventEmitters this behaves exactly the same as calling .getMaxListeners on the emitter.

For EventTargets this is the only way to get the max event listeners for the event target. If the number of event handlers on a single EventTarget exceeds the max set, the EventTarget will print a warning.

import { getMaxListeners, setMaxListeners, EventEmitter } from 'node:events';

{
  const ee = new EventEmitter();
  console.log(getMaxListeners(ee)); // 10
  setMaxListeners(11, ee);
  console.log(getMaxListeners(ee)); // 11
}
{
  const et = new EventTarget();
  console.log(getMaxListeners(et)); // 10
  setMaxListeners(11, et);
  console.log(getMaxListeners(et)); // 11
}

Parameters

Name	Type
`emitter`	`EventEmitter` \| `_DOMEventTarget`

Returns

number

Since

v18.17.0

Inherited from

EventEmitter.getMaxListeners

Defined in

node_modules/@types/node/events.d.ts:328

listenerCount

▸ listenerCount(emitter, eventName): number

A class method that returns the number of listeners for the given eventNameregistered on the given emitter.

const { EventEmitter, listenerCount } = require('events');
const myEmitter = new EventEmitter();
myEmitter.on('event', () => {});
myEmitter.on('event', () => {});
console.log(listenerCount(myEmitter, 'event'));
// Prints: 2

Parameters

Name	Type	Description
`emitter`	`EventEmitter`	The emitter to query
`eventName`	`string` \| `symbol`	The event name

Returns

number

Since

v0.9.12

Deprecated

Since v3.2.0 - Use listenerCount instead.

Inherited from

EventEmitter.listenerCount

Defined in

node_modules/@types/node/events.d.ts:271

on

▸ on(emitter, eventName, options?): AsyncIterableIterator<any>

const { on, EventEmitter } = require('events');

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo')) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

Returns an AsyncIterator that iterates eventName events. It will throw if the EventEmitter emits 'error'. It removes all listeners when exiting the loop. The value returned by each iteration is an array composed of the emitted event arguments.

An AbortSignal can be used to cancel waiting on events:

const { on, EventEmitter } = require('events');
const ac = new AbortController();

(async () => {
  const ee = new EventEmitter();

  // Emit later on
  process.nextTick(() => {
    ee.emit('foo', 'bar');
    ee.emit('foo', 42);
  });

  for await (const event of on(ee, 'foo', { signal: ac.signal })) {
    // The execution of this inner block is synchronous and it
    // processes one event at a time (even with await). Do not use
    // if concurrent execution is required.
    console.log(event); // prints ['bar'] [42]
  }
  // Unreachable here
})();

process.nextTick(() => ac.abort());

Parameters

Name	Type	Description
`emitter`	`EventEmitter`	-
`eventName`	`string`	The name of the event being listened for
`options?`	`StaticEventEmitterOptions`	-

Returns

AsyncIterableIterator<any>

that iterates eventName events emitted by the emitter

Since

v13.6.0, v12.16.0

Inherited from

EventEmitter.on

Defined in

node_modules/@types/node/events.d.ts:254

▸ on<Emitter, Events>(eventEmitter, eventName): AsyncIterableIterator<Emitter extends Client<boolean> ? ClientEvents[Events] : any>

Type parameters

Name	Type
`Emitter`	extends `__module`
`Events`	extends keyof `ClientEvents`

Parameters

Name	Type
`eventEmitter`	`Emitter`
`eventName`	`Emitter` extends `Client`<`boolean`> ? `Events` : `string`

Returns

AsyncIterableIterator<Emitter extends Client<boolean> ? ClientEvents[Events] : any>

Inherited from

EventEmitter.on

Defined in

node_modules/discord.js/typings/index.d.ts:243

once

▸ once(emitter, eventName, options?): Promise<any[]>

Creates a Promise that is fulfilled when the EventEmitter emits the given event or that is rejected if the EventEmitter emits 'error' while waiting. The Promise will resolve with an array of all the arguments emitted to the given event.

This method is intentionally generic and works with the web platform EventTarget interface, which has no special'error' event semantics and does not listen to the 'error' event.

const { once, EventEmitter } = require('events');

async function run() {
  const ee = new EventEmitter();

  process.nextTick(() => {
    ee.emit('myevent', 42);
  });

  const [value] = await once(ee, 'myevent');
  console.log(value);

  const err = new Error('kaboom');
  process.nextTick(() => {
    ee.emit('error', err);
  });

  try {
    await once(ee, 'myevent');
  } catch (err) {
    console.log('error happened', err);
  }
}

run();

The special handling of the 'error' event is only used when events.once()is used to wait for another event. If events.once() is used to wait for the 'error' event itself, then it is treated as any other kind of event without special handling:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();

once(ee, 'error')
  .then(([err]) => console.log('ok', err.message))
  .catch((err) => console.log('error', err.message));

ee.emit('error', new Error('boom'));

// Prints: ok boom

An AbortSignal can be used to cancel waiting for the event:

const { EventEmitter, once } = require('events');

const ee = new EventEmitter();
const ac = new AbortController();

async function foo(emitter, event, signal) {
  try {
    await once(emitter, event, { signal });
    console.log('event emitted!');
  } catch (error) {
    if (error.name === 'AbortError') {
      console.error('Waiting for the event was canceled!');
    } else {
      console.error('There was an error', error.message);
    }
  }
}

foo(ee, 'foo', ac.signal);
ac.abort(); // Abort waiting for the event
ee.emit('foo'); // Prints: Waiting for the event was canceled!

Parameters

Name	Type
`emitter`	`_NodeEventTarget`
`eventName`	`string` \| `symbol`
`options?`	`StaticEventEmitterOptions`

Returns

Promise<any[]>

Since

v11.13.0, v10.16.0

Inherited from

EventEmitter.once

Defined in

node_modules/@types/node/events.d.ts:194

▸ once(emitter, eventName, options?): Promise<any[]>

Parameters

Name	Type
`emitter`	`_DOMEventTarget`
`eventName`	`string`
`options?`	`StaticEventEmitterOptions`

Returns

Promise<any[]>

Inherited from

EventEmitter.once

Defined in

node_modules/@types/node/events.d.ts:195

▸ once<Emitter, Event>(eventEmitter, eventName): Promise<Emitter extends Client<boolean> ? ClientEvents[Event] : any[]>

Type parameters

Name	Type
`Emitter`	extends `__module`
`Event`	extends keyof `ClientEvents`

Parameters

Name	Type
`eventEmitter`	`Emitter`
`eventName`	`Emitter` extends `Client`<`boolean`> ? `Event` : `string`

Returns

Promise<Emitter extends Client<boolean> ? ClientEvents[Event] : any[]>

Inherited from

EventEmitter.once

Defined in

node_modules/discord.js/typings/index.d.ts:239

payload

▸ payload<T>(type, module?, reason?): T

Type parameters

Name	Type
`T`	extends `Payload`

Parameters

Name	Type
`type`	`PayloadType`
`module?`	`Module`
`reason?`	`unknown`

Returns

T

Defined in

src/core/structures/sern-emitter.ts:46

setMaxListeners

▸ setMaxListeners(n?, ...eventTargets): void

const {
  setMaxListeners,
  EventEmitter
} = require('events');

const target = new EventTarget();
const emitter = new EventEmitter();

setMaxListeners(5, target, emitter);

Parameters

Name	Type	Description
`n?`	`number`	A non-negative number. The maximum number of listeners per `EventTarget` event.
`...eventTargets`	(`EventEmitter` \| `_DOMEventTarget`)[]	-

Returns

void

Since

v15.4.0

Inherited from

EventEmitter.setMaxListeners

Defined in

node_modules/@types/node/events.d.ts:346

success

▸ success(module): Object

Creates a compliant SernEmitter module success payload

Parameters

Name	Type
`module`	`Module`

Returns

Object

Name	Type
`module`	`AnyModule`
`type`	`Success`

Defined in

src/core/structures/sern-emitter.ts:72

warning

▸ warning(reason): Object

Creates a compliant SernEmitter module warning payload

Parameters

Name	Type
`reason`	`unknown`

Returns

Object

Name	Type
`reason`	`string`
`type`	`Warning`

Defined in

src/core/structures/sern-emitter.ts:82

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Hierarchy

Constructors

constructor

Returns

Overrides

Defined in

Properties

captureRejectionSymbol

Inherited from

Defined in

captureRejections

Inherited from

Defined in

defaultMaxListeners

Inherited from

Defined in

errorMonitor

Inherited from

Defined in

Methods

addListener

Parameters

Returns

Inherited from

Defined in

emit

Type parameters

Parameters

Returns

Overrides

Defined in

eventNames

Returns

Inherited from

Defined in

getMaxListeners

Returns

Inherited from

Defined in

listenerCount

Parameters

Returns

Inherited from

Defined in

listeners

Parameters

Returns

Inherited from

Defined in

off

Parameters

Returns

Inherited from

Defined in

on

Type parameters

Parameters

Returns

Overrides

Defined in

once

Type parameters

Parameters

Returns

Overrides

Defined in

prependListener

Parameters

Returns

Inherited from

Defined in

prependOnceListener

Parameters

Returns

Inherited from

Defined in

rawListeners

Parameters

Returns

26 KiB

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