For your first issue, you need to create a polymorphic VI. <b>Quote from the online help:</b> "Polymorphic VIs accept different data types for a single input or output terminal. A polymorphic VI is a collection of subVIs with the same connector pane patterns. Each subVI is an instance of the polymorphic VI."
Basically, you must create seperate VIs for each possible input, then combine them into a polymorphic VI. Could you give a bit more details about your second question? It is not clear to me what you want to do. About your comment about "LabVIEW as General purpose language", please have a look at <a href=http://www.ni.com/devzone/lvzone/view_archived1.htm>this article</a>
