Revision 417127 of while

<h2 id="Summary" name="Summary">Summary</h2>
<p>Creates a loop that executes a specified statement as long as the test condition evaluates to true. The condition is evaluated before executing the statement.</p>
<table class="standard-table">
  <tbody>
    <tr>
      <td class="header" colspan="2">Statement</td>
    </tr>
    <tr>
      <td>Implemented in</td>
      <td>JavaScript 1.0</td>
    </tr>
    <tr>
      <td>ECMAScript Edition</td>
      <td>ECMA-262</td>
    </tr>
  </tbody>
</table>
<h2 id="Syntax" name="Syntax">Syntax</h2>
<pre class="syntaxbox">
while (<em>condition</em>) {
  <em>statement</em>
}</pre>
<h3 id="Parameters" name="Parameters">Parameters</h3>
<dl>
  <dt>
    <code>condition</code></dt>
  <dd>
    An expression evaluated before each pass through the loop. If this condition evaluates to true, <code>statement</code> is executed. When condition evaluates to false, execution continues with the statement after the <code>while</code> loop.</dd>
  <dt>
    <code>statement</code></dt>
  <dd>
    A statement that is executed as long as the condition evaluates to true. To execute multiple statements within the loop, use a <a href="/en-US/docs/JavaScript/Reference/Statements/block" title="JavaScript/Reference/Statements/block">block</a> statement (<code>{ ... }</code>) to group those statements.</dd>
</dl>
<h2 id="Examples" name="Examples">Examples</h2>
<p>The following <code>while</code> loop iterates as long as <code>n</code> is less than three.</p>
<pre class="brush:js">
var n = 0;
var x = 0;

while (n &lt; 3) {
  n++;
  x += n;
}</pre>
<p>Each iteration, the loop increments <code>n</code> and adds it to <code>x</code>. Therefore, <code>x</code> and <code>n</code> take on the following values:</p>
<ul>
  <li>After the first pass: <code>n</code> = 1 and <code>x</code> = 1</li>
  <li>After the second pass: <code>n</code> = 2 and <code>x</code> = 3</li>
  <li>After the third pass: <code>n</code> = 3 and <code>x</code> = 6</li>
</ul>
<p>After completing the third pass, the condition <code>n</code> &lt; 3 is no longer true, so the loop terminates.</p>
<h2 id="See_also" name="See_also">See also</h2>
<ul>
  <li><a href="/en-US/docs/JavaScript/Reference/Statements/do...while" title="JavaScript/Reference/Statements/do...while">do...while</a>, <a href="/en-US/docs/JavaScript/Reference/Statements/for" title="JavaScript/Reference/Statements/for">for</a></li>
</ul>
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