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Set.prototype

The Set.prototype property represents the prototype for the Set constructor.

Property attributes of `Set.prototype`
Writable	no
Enumerable	no
Configurable	no

Description

Set instances inherit from Set.prototype. You can use the constructor's prototype object to add properties or methods to all Set instances.

Properties

Set.prototype.constructor: Returns the function that created an instance's prototype. This is the Set function by default.
Set.prototype.size: Returns the number of values in the Set object.

Methods

Set.prototype.add(value): Appends a new element with the given value to the Set object. Returns the Set object.
Set.prototype.clear(): Removes all elements from the Set object.
Set.prototype.delete(value): Removes the element associated to the value and returns the value that Set.prototype.has(value) would have previously returned. Set.prototype.has(value) will return false afterwards.
Set.prototype.entries(): Returns a new Iterator object that contains an array of [value, value] for each element in the Set object, in insertion order. This is kept similar to the Map object, so that each entry has the same value for its key and value here.
Set.prototype.forEach(callbackFn[, thisArg]): Calls callbackFn once for each value present in the Set object, in insertion order. If a thisArg parameter is provided to forEach, it will be used as the this value for each callback.
Set.prototype.has(value): Returns a boolean asserting whether an element is present with the given value in the Set object or not.
Set.prototype.keys(): Is the same function as the values() function and returns a new Iterator object that contains the values for each element in the Set object in insertion order.
Set.prototype.values(): Returns a new Iterator object that contains the values for each element in the Set object in insertion order.
Set.prototype[@@iterator](): Returns a new Iterator object that contains the values for each element in the Set object in insertion order.

Specifications

Specification	Status	Comment
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Set.prototype' in that specification.	Standard	Initial definition.
ECMAScript 2017 Draft (ECMA-262) The definition of 'Set.prototype' in that specification.	Draft

Browser compatibility

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	38	13 (13)	11	25	7.1