debounce.md

Rx.Observable.prototype.debounce(dueTime, [scheduler])

Rx.Observable.prototype.debounce(durationSelector)

Ⓢ

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

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

Dist:

• rx.all.js
• rx.all.compat.js
• rx.time.js
• rx.lite.js
• rx.lite.compat.js

Prerequisites:

• If using rx.time.js
  • rx.js | rx.compat.js

NPM Packages:

• rx

NuGet Packages:

• RxJS-All
• RxJS-Lite
• RxJS-Time

Unit Tests:

• /tests/observable/debounce.js