Re: Bugs caused by recent use of define-derived-mode

[Luc Teirlinck]

>From my previous message:

   However, the variable local-abbrev-table would be complemented with a
   variable local-abbrev-table-list. `expand-abbrev' would check whether
   this variable is non-nil and, if so, use it instead of
   local-abbrev-table.  (This could be implemented in C, or in Lisp,
   using pre-abbrev-expand-hook.)

Actually, implementing this in Lisp using pre-abbrev-expand-hook might
be tricky, since one would have to make completely sure that other
functions wanting to change or override abbrev-expansion get a chance
to run before the function implementing this variable. One can put it
at the end of pre-abbrev-expand-hook using the APPEND argument of
add-hook, but one then better hope that something else is not
going to override this.  I do not know how easy or difficult the
implementation in C is.  I know C, but am not very familiar with
Emacs' C internals.

Some other problems may need to be looked into.

Anyway, the first question to decide is: 

Is it is actually worth trying to implement multiple local abbrev
tables, as a customization feature, or not?

Sincerely,

Luc.