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    Set.prototype.has()

    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.

    Summary

    The has() method returns a boolean indicating whether an element with the specified value exists in a Set object or not.

    Syntax

    mySet.has(value);

    Parameters

    value
    Required. The value to test for presence in the Set object.

    Return value

    Boolean
    Returns true if an element with the specified value exists in the Set object; otherwise false.

    Examples

    Example: Using the has method

    var mySet = new Set();
    mySet.add("foo");
    
    mySet.has("foo");  // returns true
    mySet.has("bar");  // returns false
    

    Specifications

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

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
    Basic support 38 13.0 (13.0) 11 25 7.1
    Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
    Basic support Not supported 38 13.0 (13.0) Not supported Not supported iOS 8

    See also

    Document Tags and Contributors

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