Code review comment for lp:~davidagraf/zorba/trace_without_debug_info

Hello Chris
Here is the current work I've done to remove the debug output in fn:trace (as discussed in the email with markos). It's working fine. But I need some advice to make it better. I am doing this via a merge request. I think that's easier for you because I can see the diff.
In the current implementation, I am doing two nasty things:
1) The code to print an attribute is redundant. That's bad. Would it make sense to add an option to the serializer to enable printing of all nodes? I am not sure. Especially because it is not so easy to do. All the emmitter need to be changed. Do you see a nicer solution?
2) If the node is not an attribute, I create a serializer in each iteration! Although I always need the same. But I didn't find a nice solution to use just one serializer. If I do a singleton, I need to create the serializer on the heap. If I put the seralizer as a member in the state or the iterator, I need to import the serializer in the header file.
Best
David