Has anyone received an error in Flash Builder like this?

Question

access of undefined property variable01.
access of undefined property pattern.
I don't see a problem with the code, yet the error persists.
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
               xmlns:s="library://ns.adobe.com/flex/spark"
               xmlns:mx="library://ns.adobe.com/flex/mx"
               creationComplete="init(event);"
               minWidth="955" minHeight="600" backgroundColor="#cbd8e6">
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
    <fx:Script>
        <![CDATA[
        var variable01:String;
        variable01 = "1";
        var pattern:RegExp;
        pattern = /^[0-9]{1,3}$/;
        pattern.test(variable01);
        ]]>
    </fx:Script>
</s:Application>

Answer 1

When using Flex you can't just put code in a script tag like this. While declarations (public var etc) can be in this scope, logic must be inside an event handler.
See my answer in this thread:
http://forums.adobe.com/thread/980259