GeneratorFunction

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.

TheGeneratorFunction object provides methods forgenerator functions. In JavaScript, every generator function is actually aGeneratorFunction object.

Note thatGeneratorFunction isnot a global object. It can be obtained with the following code:

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

GeneratorFunction is a subclass ofFunction.

Try it

const GeneratorFunction = function* () {}.constructor;const foo = new GeneratorFunction(`  yield 'a';  yield 'b';  yield 'c';`);let str = "";for (const val of foo()) {  str += val;}console.log(str);// Expected output: "abc"

Constructor

GeneratorFunction(): Creates a newGeneratorFunction object.

Instance properties

Also inherits instance properties from its parentFunction.

These properties are defined onGeneratorFunction.prototype and shared by allGeneratorFunction instances.

GeneratorFunction.prototype.constructor: The constructor function that created the instance object. ForGeneratorFunction instances, the initial value is theGeneratorFunction constructor.
GeneratorFunction.prototype.prototype: All generator functions share the sameprototype property, which isGenerator.prototype. Each generator function created with thefunction* syntax or theGeneratorFunction() constructor also has its ownprototype property, whose prototype isGeneratorFunction.prototype.prototype. When the generator function is called, itsprototype property becomes the prototype of the returned generator object.
GeneratorFunction.prototype[Symbol.toStringTag]: The initial value of the[Symbol.toStringTag] property is the string"GeneratorFunction". This property is used inObject.prototype.toString().