I just ran into a disturbing bug today: declaring and assigning an XMLList in one line inside a switch statement fails. The best available description is here - note that enclosing the content of the "case" inside curly braces makes thing work (sounds like a parser problem).
This may be related to http://bugs.adobe.com/jira/browse/ASC-2901, or maybe one of these in http://bugs.adobe.com/jira/browse/ASC-3644.
Either way, this is not the first time we are having funny things with switch statements - ASC really looks bad on that :-(