[Texmacs-dev] file-exists? name conflict (was: Bad crash)

[David Allouche]

On Wed, May 07, 2003 at 09:18:22AM +0200, David Allouche wrote:
> On Tue, May 06, 2003 at 05:58:12PM -0600, Nix N. Nix wrote:
> > I tried to compile TeXmacs from source on RedHat9.  It compiled just
> > fine, but when I tried to run it, it completely crashed and burnt with
> > guile errors.  I assume the code does not work with guile 1.6.0.
> > 
> > This is really bad, because I cannot run TeXmacs when compiled from
> > source, and I cannot seem to get guile 1.4 to compile.
> > 
> > TeXmacs] Loading ecrm11 at 300 dpi
> > /usr/share/TeXmacs-1.0.1.12/progs/core/texmacs/tm-preferences.scm:113:7:
> > In expression (file-exists? "$TEXMACS_HOME_PATH/system"
> > "preferences.scm"):
> > /usr/share/TeXmacs-1.0.1.12/progs/core/texmacs/tm-preferences.scm:113:7:
> > Wrong number of arguments to #<procedure file-exists? (str)>
> 
> Humm... that looks like a problem related to patch #1405.
[..] 
> I cannot see what may be causing this problem. Maybe texmacs
> mis-detects the guile-dialect at configure time...

By looking that your patch, I can see that guile-dialect detection is
not the problem (your fix affects the guile-b branch of the dialect
test).

Yet I am unsure that is really correct.

Here the old code:

(if (guile-a?)
    (set! file-exists?
          (let ((guile-file-exists? file-exists?))
            (lambda args
              (if (null? (cdr args))
                  (apply guile-file-exists? args)
                  (apply texmacs-file-exists? args)))))
    (define file-exists? texmacs-file-exists?))

Here the new code:

(if (guile-a?)
    (set! file-exists?
          [same stuff here]
    (set! file-exists? texmacs-file-exists?))

The problem is, if not guile-a? then symbol 'file-exists?' is
supposedly not bound at this point. So 'set!' is not really correct.

Actually, the problem with set! is that you may be setting a variable
in the guile module (which is always visible) thus reverting back to
the name conflict situation we had before: internal guile functions
are using texmacs-file-exists? instead of guile's primitive.

But the problem with 'define' may be that a binding is created in the
module (core boot compat) and not exported to (guile-user).

In addition, since the binding is *not always* created in (core boot
compat), we may not add 'file-exists?' to the public interface of the
module without breaking the current convention that a module interface
is completely set in the texmacs-module expression.

Well maybe we could do so... but exporting a symbol which is not
defined in the current module is not really what I would call clean.

So the correct fix is probably to load compat.scm with
    (exec-file "$TEXMACS_PATH/progs/core/boot" "compat.scm")
instead of inherit-modules.

-- 
                                                            -- ddaa