[developers] morphology - testing and a couple more things

[Ann Copestake]

Official testers - please take this as a request to test if you haven't already
done so!  I have had no feedback whatsoever about the revised code.  I am not
sure whether that simply means nobody has tried it on their grammars.  If you
have tried it, and it works, please let me know that too.  It is important
it gets tested reasonably soon because it's very difficult for me to find time
to fix bugs during term time, plus I'll forget the details of the code.

I thought I'd allowed for every case of escaping in the code, but I didn't
think of people wanting to name letter sets !, ?, *, \ or ).  Rather than
changing things again, and complicating the code some more, I would just ask
people to avoid using those characters as the names of letter sets and not to
put escapes inside letter set specifications in any context.  I'm afraid I
think this means the checked in version of the ERG may not work because it has
!\?. The fixes I have made to it in my local version are to rename !?, to get
rid of !b (which was giving an unmatched letter set warning, although that's
not fatal) and to not load the file with the double escape characters.

The other thing I thought I should mention is that because the rule table no
longer gets built using all rules, you will not get warnings of possibly cyclic
applications of rules which have a morphological effect.  This is nevertheless
something that should be avoided when it is impossible, since it will lead to
unnecessary analyses being tried and may give some spurious parses.  If it's
thought useful, I can easily make it possible to check all feeding
relationships - e.g., make it a menu option.  Let me know.

Ann