This is probably a nub question, but I don't understand why this works:

<script type="text/javascript">
    alert(foo);
    function foo() { }
</script>

This alerts "function foo() { }", but I expected the alert to be evaluated before the function foo was defined. Can someone explain what I don't understand about parse/evaluation order or point me to a resource that does?

Thanks in advance,

-- Breck