ted.
The expression is evaluated before each iteration of the loop.
</p>
<p>
The <i>while</i> loop terminates in the following cases:
<ul>
	<li>The <i>expression</i> does not hold true</li>
	<li>A <a href="query_script_break.html">break</a> statement is executed inside the loop (but not inside a nested loop)</li>
	<li>A <a href="query_script_return.html">return</a> statement is executed inside the loop</li>
	<li>An uncaught error is raised (at the moment all errors are by default uncaught unless handled in 