GeneratorFunction

BaselineWidely 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().