Problem with the Centaur/Emacs text editing interface

[Guido.Bosch@loria.fr (Guido Bosch)]

Hi,

I have encountered the following (non technical) problem while using
the Centaur/Emacs editing interface:

I use Centaur's structured editor to construct any kind of tree of my
language. I do this by putting first a metavariable tree in the ctedit
root, then I use  the Ctmenu and Emacs for develloping it further.

The problem now is that when I've chosen a tree as root that can be
directly selected (i.e., it has a visible part on the ctedit window),
I can select a tree without father. When I want to edit it with Emacs,
Centaur cannot compute the entry point for the parser, so I have to
enter it by hand.

I think that there is no general algorithm that can deterministically
find the phylum whose name can be used as entry point for an arbitrary
operator, but heuristics can be imagined (maybe doing some assumptions
on the particular languge definition).

What is the function computing the entry point for text editing
that I had to redefine in order to experience with different
heuristics? 

	Guido