Reactive-Extensions/RxJS

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doc/api/core/operators/debounce.md

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# This is RxJS v 4. [Find the latest version here](https://github.com/reactivex/rxjs)
### `Rx.Observable.prototype.debounce(dueTime, [scheduler])` ###
### `Rx.Observable.prototype.debounce(durationSelector)` ###
[Ⓢ](https://github.com/Reactive-Extensions/RxJS/blob/master/src/core/linq/observable/debounce.js "View in source")
 
Emits an item from the source Observable after a particular timespan has passed without the Observable omitting any other items.
 
--OR--
 
Ignores values from an observable sequence which are followed by another value within a computed debounced duration.
 
#### Arguments
 
If using a relative due time:
1. `dueTime` *(`Number`)*: Duration of the throttle period for each value (specified as an integer denoting milliseconds).
2. `[scheduler]` *(`Any`)*: Scheduler to run the throttle timers on. If not specified, the default scheduler is used.
 
If using the duration selector function:
1. `durationSelector` *(`Function`)*: Selector function to retrieve a sequence indicating the throttle duration for each given element.
 
#### Returns
*(`Observable`)*: The debounced sequence.
 
#### Example
```js
var times = [
{ value: 0, time: 100 },
{ value: 1, time: 600 },
{ value: 2, time: 400 },
{ value: 3, time: 700 },
{ value: 4, time: 200 }
];
 
// Delay each item by time and project value;
var source = Rx.Observable.from(times)
.flatMap(function (item) {
return Rx.Observable
.of(item.value)
.delay(item.time);
})
.debounce(500 /* ms */);
 
var subscription = source.subscribe(
function (x) {
console.log('Next: %s', x);
},
function (err) {
console.log('Error: %s', err);
},
function () {
console.log('Completed');
});
 
// => Next: 3
// => Completed
 
/* Using Selector */
var array = [
800,
700,
600,
500
];
 
var source = Rx.Observable.for(
array,
function (x) { return Rx.Observable.timer(x) }
)
.map(function(x, i) { return i; })
.debounce(function (x) { return Rx.Observable.timer(700); });
 
var subscription = source.subscribe(
function (x) {
console.log('Next: %s', x);
},
function (err) {
console.log('Error: %s', err);
},
function () {
console.log('Completed');
});
 
// => Next: 0
// => Next: 3
// => Completed
```
 
### Location
 
File:
- [`/src/core/linq/observable/debounce.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/src/core/linq/observable/debounce.js)
 
Dist:
- [`rx.all.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.all.js)
- [`rx.all.compat.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.all.compat.js)
- [`rx.time.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.time.js)
- [`rx.lite.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.lite.js)
- [`rx.lite.compat.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.lite.compat.js)
 
Prerequisites:
- If using `rx.time.js`
- [`rx.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.js) | [`rx.compat.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/dist/rx.compat.js)
 
NPM Packages:
- [`rx`](https://www.npmjs.org/package/rx)
 
NuGet Packages:
- [`RxJS-All`](http://www.nuget.org/packages/RxJS-All/)
- [`RxJS-Lite`](http://www.nuget.org/packages/RxJS-Lite/)
- [`RxJS-Time`](http://www.nuget.org/packages/RxJS-Time/)
 
Unit Tests:
- [`/tests/observable/debounce.js`](https://github.com/Reactive-Extensions/RxJS/blob/master/tests/observable/debounce.js)