isempty.md

This is RxJS v 4. Find the latest version here

Rx.Observable.prototype.isEmpty()

Ⓢ

Determines whether an observable sequence is empty.

Returns

(Observable): An observable sequence containing a single element determining whether the source sequence is empty.

Example

/* Not empty */
var source = Rx.Observable.range(0, 5)
    .isEmpty()

var subscription = source.subscribe(
    function (x) {
        console.log('Next: ' + x);
    },
    function (err) {
        console.log('Error: ' + err);
    },
    function () {
        console.log('Completed');
    });

// => Next: false
// => Completed

/* Empty */
var source = Rx.Observable.empty()
    .isEmpty()

var subscription = source.subscribe(
    function (x) {
        console.log('Next: ' + x);
    },
    function (err) {
        console.log('Error: ' + err);
    },
    function () {
        console.log('Completed');
    });

// => Next: true
// => Completed

Location

File:

• /src/core/linq/observable/isempty.js

Dist:

• rx.all.js
• rx.all.compat.js
• rx.aggregates.js

Prerequisites:

• rx.js | rx.compat.js | rx.lite.js | rx.lite.compat.js

NPM Packages:

• rx

NuGet Packages:

• RxJS-All
• RxJS-Aggregates

Unit Tests:

• /tests/observable/isempty.js