bug#24439: ispell.el; cutom setting `ispell-library-directory'; patch

[Eli Zaretskii]

> From: Laimonas Vėbra <laimonas.vebra@yahoo.com>
> Date: Wed, 14 Sep 2016 23:02:03 +0300
> 
> On Windows if one uses cygwin ispell, then one should fix ispell LIBDIR 
> (which is not correct absolute path) relative to cygwin root by setting 
> `ispell-library-directory'. Or one also might wish to use custom 
> location of dictionaries.

ispell-library-directory is not supposed to be customized by users,
it's an internal variable set and used by ispell.el.  To change the
location of dictionaries, users are supposed to customize
ispell-local-dictionary-alist.  Why can't you do that instead?

> Currently ispell.el breaks this possibiliity, because it resets
> `ispell-library-directory' to possibly incorrect or unwanted ispell 
> LIBDIR on every ispell call.

That's not what I see.  What I see is that ispell-library-directory is
set once whenever the ispell process is created, which happens only
once in a session, or when you change your ispell dictionary.  So I
think this is completely justified, because the user could install
additional dictionaries before restarting ispell.

> Could someone familiar with ispell.el overview and comment on this tiny 
> patch?

I would prefer not to mess with the internal workings of ispell.el, if
possible.

If the suggestions above don't solve your problems, perhaps you could
write a batch file or a script which reported the library directory in
the format that ispell.el expects in a native Windows build of Emacs.
Or maybe you could switch to Hunspell or Aspell, which don't need
ispell-library-directory at all.  A native Windows port of Hunspell is
available (and works very well for me).

Thanks.