function* expression

The function* keyword can be used to define a generator function inside an expression.

Syntax

function* [name]([param1[, param2[, ..., paramN]]]) {
  statements
}

Parameters

name Optional

The function name. Can be omitted, in which case the function is anonymous. The name is only local to the function body.

paramN Optional

The name of an argument to be passed to the function. A function can have up to 255 arguments.

statements

The statements which comprise the body of the function.

Description

A function* expression is very similar to and has almost the same syntax as a function* statement. The main difference between a function* expression and a function* statement is the function name, which can be omitted in function* expressions to create anonymous generator functions. See also the chapter about functions for more information.

Examples

Using function*

The following example defines an unnamed generator function and assigns it to x. The function yields the square of its argument:

let x = function*(y) {
   yield y * y;
};

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
function*
49
12
26
No
36
10
49
49
26
36
10
5.0
trailing_comma
58
79
52
No
45
10
58
58
52
43
10
7.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/function*