[Legorol]

I agree that hooking into the __index function is a good way to see method calls at run time, and can make tracing based on patterns work. I presume what you had in mind is that if the user has specified a regexp, then you don't hook there and then, but if you notice a method call that matches the regexp, then you hook it. That would work and in fact sounds like a good idea for being able to use regexp patterns with XML-generated tables. The particular example I was thinking of is specifying a trace pattern such as GameTooltip%.Set.+ (i mean to indicate that the first '.' is not special but the second one is, i don't know what's the best way for you to handle this).

Unfortunately hooking __index will not help with scanning for the API, because it would require you to actually run WoW and wait for all sorts of method calls to actually happen for you to be able to see that they exist. There are some methods that are in fact never called from any of the default Blizzard UI files, and therefore would be missed, even if you made use of every UI element. One such example is the FontString:SetJustifyV method.

The list on the Wiki is generated by a very crude and simple method: scan WoW.exe for all strings and make a list out if, which forms the list of candidates. Then test each object type and see if it has a method that is named any of those candidates. The key here is that testing for a superset that includes stuff other than valid method names is not a problem as long as your set is guaranteed to include all actual methods.

OO

Supporting OO concepts in TraceEvent is going to be tricky in my opinion. Although there are one or two 'standard' text-book ways of doing OO (classes and instances) in Lua using tables, there are actually a number of possible ways of implementing OO or semi-OO concepts. I have seen different AddOns use very different means to implement OO concepts such as classes and instanciation. Catering for all these scenarios will be difficult, because you won't know in what particular way is an AddOn making use of metatables for example.

This is just my opinion, but I beleive that you should drop the ':' syntax alltogether and not try to cater for OO concepts at all. Instead, make sure you have a firm method of tracing table elements, using the '.' syntax. That should be sufficient for those using OO concepts, because they can either specify the table representing the class, or the table representing an instance if they wish. This is just my personal opinion though.