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GeneratorFunction() constructor

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2016⁩.

The GeneratorFunction() constructor creates GeneratorFunction objects.

Note that GeneratorFunction is not a global object. It can be obtained with the following code:

const GeneratorFunction = function* () {}.constructor;

The GeneratorFunction() constructor is not intended to be used directly, and all caveats mentioned in the Function() description apply to GeneratorFunction().

Syntax

new GeneratorFunction(functionBody)
new GeneratorFunction(arg1, functionBody)
new GeneratorFunction(arg1, arg2, functionBody)
new GeneratorFunction(arg1, arg2, /* …, */ argN, functionBody)

GeneratorFunction(functionBody)
GeneratorFunction(arg1, functionBody)
GeneratorFunction(arg1, arg2, functionBody)
GeneratorFunction(arg1, arg2, /* …, */ argN, functionBody)

Note: GeneratorFunction() can be called with or without new. Both create a new GeneratorFunction instance.

Parameters

See Function().

Examples

Creating and using a GeneratorFunction() constructor

const GeneratorFunction = function* () {}.constructor;
const g = new GeneratorFunction("a", "yield a * 2");
const iterator = g(10);
console.log(iterator.next().value); // 20

Specifications

Specification
ECMAScript® 2026 Language Specification> # sec-generatorfunction-constructor>

Browser compatibility

	Desktop					Mobile							Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS	Bun	Deno	Node.js
`GeneratorFunction`	39	13	26	26	10	39	26	26	10	4.0	39	10	1.0.0	1.0	4.0.0