doc: add `added:` information for events

doc: add `added:` information for events · nodejs/node@769f63c

@@ -167,6 +167,9 @@ myEmitter.emit('error', new Error('whoops!'));

167167```168168169169## Class: EventEmitter170+170173171174The `EventEmitter` class is defined and exposed by the `events` module:172175

@@ -178,6 +181,9 @@ All EventEmitters emit the event `'newListener'` when new listeners are

178181added and `'removeListener'` when existing listeners are removed.179182180183### Event: 'newListener'184+181187182188* `eventName` {String|Symbol} The name of the event being listened for183189* `listener` {Function} The event handler function

@@ -214,13 +220,20 @@ myEmitter.emit('event');

214220```215221216222### Event: 'removeListener'223+217226218227* `eventName` {String|Symbol} The event name219228* `listener` {Function} The event handler function220229221230The `'removeListener'` event is emitted *after* the `listener` is removed.222231223232### EventEmitter.listenerCount(emitter, eventName)233+224237225238> Stability: 0 - Deprecated: Use [`emitter.listenerCount()`][] instead.226239

@@ -236,6 +249,9 @@ console.log(EventEmitter.listenerCount(myEmitter, 'event'));

236249```237250238251### EventEmitter.defaultMaxListeners252+239255240256By default, a maximum of `10` listeners can be registered for any single241257event. This limit can be changed for individual `EventEmitter` instances

@@ -263,10 +279,16 @@ emitter.once('event', () => {

263279```264280265281### emitter.addListener(eventName, listener)282+266285267286Alias for `emitter.on(eventName, listener)`.268287269288### emitter.emit(eventName[, arg1][, arg2][, ...])289+270292271293Synchronously calls each of the listeners registered for the event named272294`eventName`, in the order they were registered, passing the supplied arguments

@@ -275,6 +297,9 @@ to each.

275297Returns `true` if the event had listeners, `false` otherwise.276298277299### emitter.eventNames()300+278303279304Returns an array listing the events for which the emitter has registered280305listeners. The values in the array will be strings or Symbols.

@@ -293,18 +318,27 @@ console.log(myEE.eventNames());

293318```294319295320### emitter.getMaxListeners()321+296324297325Returns the current max listener value for the `EventEmitter` which is either298326set by [`emitter.setMaxListeners(n)`][] or defaults to299327[`EventEmitter.defaultMaxListeners`][].300328301329### emitter.listenerCount(eventName)330+302333303334* `eventName` {String|Symbol} The name of the event being listened for304335305336Returns the number of listeners listening to the event named `eventName`.306337307338### emitter.listeners(eventName)339+308342309343Returns a copy of the array of listeners for the event named `eventName`.310344

@@ -317,6 +351,9 @@ console.log(util.inspect(server.listeners('connection')));

317351```318352319353### emitter.on(eventName, listener)354+320357321358* `eventName` {String|Symbol} The name of the event.322359* `listener` {Function} The callback function

@@ -350,6 +387,9 @@ myEE.emit('foo');

350387```351388352389### emitter.once(eventName, listener)390+353393354394* `eventName` {String|Symbol} The name of the event.355395* `listener` {Function} The callback function

@@ -380,6 +420,9 @@ myEE.emit('foo');

380420```381421382422### emitter.prependListener(eventName, listener)423+383426384427* `eventName` {String|Symbol} The name of the event.385428* `listener` {Function} The callback function

@@ -399,6 +442,9 @@ server.prependListener('connection', (stream) => {

399442Returns a reference to the `EventEmitter`, so that calls can be chained.400443401444### emitter.prependOnceListener(eventName, listener)445+402448403449* `eventName` {String|Symbol} The name of the event.404450* `listener` {Function} The callback function

@@ -416,6 +462,9 @@ server.prependOnceListener('connection', (stream) => {

416462Returns a reference to the `EventEmitter`, so that calls can be chained.417463418464### emitter.removeAllListeners([eventName])465+419468420469Removes all listeners, or those of the specified `eventName`.421470

@@ -426,6 +475,9 @@ component or module (e.g. sockets or file streams).

426475Returns a reference to the `EventEmitter`, so that calls can be chained.427476428477### emitter.removeListener(eventName, listener)478+429481430482Removes the specified `listener` from the listener array for the event named431483`eventName`.

@@ -490,6 +542,9 @@ the `emitter.listeners()` method will need to be recreated.

490542Returns a reference to the `EventEmitter`, so that calls can be chained.491543492544### emitter.setMaxListeners(n)545+493548494549By default EventEmitters will print a warning if more than `10` listeners are495550added for a particular event. This is a useful default that helps finding