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generator.return

The return() method returns the given value and finishes the generator.

Syntax

gen.return(value)

Parameters

value
The value to return.

Return value

The value that is given as an argument.

Examples

Using return()

The following example shows a simple generator and the return method.

function* gen() { 
  yield 1;
  yield 2;
  yield 3;
}

const g = gen();

g.next();        // { value: 1, done: false }
g.return('foo'); // { value: "foo", done: true }
g.next();        // { value: undefined, done: true }

If return(value) is called on a generator that is already in "completed" state, the generator will remain in "completed" state.

If no argument is provided, the value property of returned object is the same as if .next(). If an argument is provided, it will be set to the value of the value property of the returned object.

function* gen() {
  yield 1;
  yield 2;
  yield 3;
}

const g = gen();
g.next(); // { value: 1, done: false }
g.next(); // { value: 2, done: false }
g.next(); // { value: 3, done: false }
g.next(); // { value: undefined, done: true }
g.return(); // { value: undefined, done: true }
g.return(1); // { value: 1, done: true }

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
return 50 13 38 No 37 10
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
return 50 50 38 37 10 5.0
Server
Node.js
return 6.0.0

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Generator/return