Revision 703121 of Set.prototype

<div>
 {{JSRef("Global_Objects", "Set")}} {{harmony()}}</div>
<h2 id="Summary" name="Summary">Summary</h2>
<p>The <code><strong>Set</strong></code><strong><code>.prototype</code></strong> property represents the prototype for the {{jsxref("Set")}} constructor.</p>
<div>
 {{js_property_attributes(0,0,0)}}</div>
<h2 id="Description" name="Description">Description</h2>
<p>{{jsxref("Set")}} instances inherit from {{jsxref("Set.prototype")}}. You can use the constructor's prototype object to add properties or methods to all <code>Set</code> instances.</p>
<h2 id="Properties">Properties</h2>
<dl>
 <dt>
  <code>Set.prototype.constructor</code></dt>
 <dd>
  Returns the function that created an instance's prototype. This is the {{jsxref("Set")}} function by default.</dd>
 <dt>
  {{jsxref("Set.prototype.size")}}</dt>
 <dd>
  Returns the number of values in the <code>Set</code> object.</dd>
</dl>
<h2 id="Methods">Methods</h2>
<dl>
 <dt>
  {{jsxref("Set.add", "Set.prototype.add(value)")}}</dt>
 <dd>
  Appends a new element with the given value to the <code>Set</code> object. Returns the <code>Set</code> object.</dd>
 <dt>
  {{jsxref("Set.prototype.clear()")}}</dt>
 <dd>
  Removes all elements from the <code>Set</code> object.</dd>
 <dt>
  {{jsxref("Set.delete", "Set.prototype.delete(value)")}}</dt>
 <dd>
  Removes the element associated to the <code>value</code> and returns the value that <code>Set.prototype.has(value)</code> would have previously returned. <code>Set.prototype.has(value)</code> will return <code>false</code> afterwards.</dd>
 <dt>
  {{jsxref("Set.prototype.entries()")}}</dt>
 <dd>
  Returns a new <code>Iterator</code> object that contains<strong> an array of <code>[value, value]</code></strong> for each element in the <code>Set</code> object, in insertion order. This is kept similar to the <code>Map</code> object, so that each entry has the same value for its <em>key</em> and <em>value</em> here.</dd>
 <dt>
  {{jsxref("Set.forEach", "Set.prototype.forEach(callbackFn[, thisArg])")}}</dt>
 <dd>
  Calls <code>callbackFn</code> once for each value present in the <code>Set</code> object, in insertion order. If a <code>thisArg</code> parameter is provided to <code>forEach</code>, it will be used as the <code>this</code> value for each callback.</dd>
 <dt>
  {{jsxref("Set.has", "Set.prototype.has(value)")}}</dt>
 <dd>
  Returns a boolean asserting whether an element is present with the given value in the <code>Set</code> object or not.</dd>
 <dt>
  {{jsxref("Set.prototype.keys()")}}</dt>
 <dd>
  Is the same function as the <strong><code>values()</code></strong> function and returns a new <code>Iterator</code> object that contains the values for each element in the <code>Set</code> object in insertion order.</dd>
 <dt>
  {{jsxref("Set.prototype.values()")}}</dt>
 <dd>
  Returns a new <code>Iterator</code> object that contains the <strong>values</strong> for each element in the <code>Set</code> object in insertion order.</dd>
 <dt>
  {{jsxref("Set.prototype.@@iterator()", "Set.prototype[@@iterator]()")}}</dt>
 <dd>
  Returns a new <code>Iterator</code> object that contains the <strong>values</strong> for each element in the <code>Set</code> object in insertion order.</dd>
</dl>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#sec-set.prototype', 'Set.prototype')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>
<h2 id="Browser_compatibility">Browser compatibility</h2>
<p>{{ CompatibilityTable() }}</p>
<div id="compat-desktop">
 <table class="compat-table">
  <tbody>
   <tr>
    <th>Feature</th>
    <th>Chrome</th>
    <th>Firefox (Gecko)</th>
    <th>Internet Explorer</th>
    <th>Opera</th>
    <th>Safari</th>
   </tr>
   <tr>
    <td>Basic support</td>
    <td>38</td>
    <td>{{ CompatGeckoDesktop("13") }}</td>
    <td>11</td>
    <td>25</td>
    <td>7.1</td>
   </tr>
  </tbody>
 </table>
</div>
<div id="compat-mobile">
 <table class="compat-table">
  <tbody>
   <tr>
    <th>Feature</th>
    <th>Android</th>
    <th>Chrome for Android</th>
    <th>Firefox Mobile (Gecko)</th>
    <th>IE Mobile</th>
    <th>Opera Mobile</th>
    <th>Safari Mobile</th>
   </tr>
   <tr>
    <td>Basic support</td>
    <td>{{ CompatNo() }}</td>
    <td>38</td>
    <td>{{ CompatGeckoMobile("13") }}</td>
    <td>{{ CompatNo() }}</td>
    <td>{{ CompatNo() }}</td>
    <td>
     <p>iOS 8</p>
    </td>
   </tr>
  </tbody>
 </table>
</div>
<h3 id="See_also"><span style="font-size: 2.142857142857143rem; font-weight: 700; letter-spacing: -1px; line-height: 30px;">See also</span></h3>
<ul>
 <li>{{jsxref("Map.prototype")}}</li>
</ul>