Hi Wouter,
The THtml class generates the USER_Index.html file with the following
algorigthm.
All class implementation file names including un underscore are put
in the same category. In the case of Root, for example, the
implementation
file names look like
BASE_*.cxx
CONT_*.cxx
..
TREE_*.cxx
All the BASE classes will be automatically assigned tp BASE_Index.html,
etc
This is OK for ROOT, all the classes being in the directory src.
This algorithm could be extended to use, for example, the subdirectory
of the implementation file.
Rene Brun