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    This is an experimental technology, part of the Harmony (ECMAScript 6) proposal.
    Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future version of browsers as the spec changes.


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

    Property attributes of WeakSet.prototype
    Writable no
    Enumerable no
    Configurable no


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


    Returns the function that created an instance's prototype. This is the WeakSet function by default.


    Appends a new element with the given value to the WeakSet object.
    Removes the element associated to the value. WeakSet.prototype.has(value) will return false afterwards.
    Returns a boolean asserting whether an element is present with the given value in the WeakSet object or not.
    Removes all elements from the WeakSet object.


    Specification Status Comment
    ECMAScript 6 (ECMA-262)
    The definition of 'WeakSet.prototype' in that specification.
    Draft Initial definition.

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support 36 34 (34) Not supported 23 Not supported
    Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support Not supported 34.0 (34) Not supported Not supported Not supported

    See also

    Document Tags and Contributors

    Contributors to this page: claudepache, realityking, fscholz, teoli
    Last updated by: fscholz,