bug#683: 23.0.60; Recursive load error stays

bug#683: 23.0.60; Recursive load error stays

[Markus Triska]

I have "~/p.el" which consists of the form:

   (load "~/p.el")

When I do:

   emacs -Q ~/p.el

and evaluate the form (C-x C-e), I get:

   Debugger entered--Lisp error: (error "Recursive load"...

as expected. Now I comment out the form:

   ;(load "~/p.el")

then save the file, and evaluate the form again. Now I again get:

   Debugger entered--Lisp error: (error "Recursive load"...

When I restart Emacs, it correctly evaluates the form.


In GNU Emacs 23.0.60.1 (i386-apple-darwin8.11.1, GTK+ Version 2.12.9)
 of 2008-08-08 on pnsgw1-client079.demo.tuwien.ac.at
Windowing system distributor `The XFree86 Project, Inc', version 11.0.40400000
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: nil
  default-enable-multibyte-characters: t

bug#683: 23.0.60; Recursive load error stays

[ＯＦＦＩＣＥ ZERO]

Do'nt   send  me mail  !!!
no tkank you!!


----- Original Message ----- 
From: "Markus Triska" <markus.triska@gmx.at>
To: <emacs-pretest-bug@gnu.org>
Sent: Sunday, August 10, 2008 7:12 AM
Subject: bug#683: 23.0.60; Recursive load error stays


>
> I have "~/p.el" which consists of the form:
>
>   (load "~/p.el")
>
> When I do:
>
>   emacs -Q ~/p.el
>
> and evaluate the form (C-x C-e), I get:
>
>   Debugger entered--Lisp error: (error "Recursive load"...
>
> as expected. Now I comment out the form:
>
>   ;(load "~/p.el")
>
> then save the file, and evaluate the form again. Now I again get:
>
>   Debugger entered--Lisp error: (error "Recursive load"...
>
> When I restart Emacs, it correctly evaluates the form.
>
>
> In GNU Emacs 23.0.60.1 (i386-apple-darwin8.11.1, GTK+ Version 2.12.9)
> of 2008-08-08 on pnsgw1-client079.demo.tuwien.ac.at
> Windowing system distributor `The XFree86 Project, Inc', version 
> 11.0.40400000
> Important settings:
>  value of $LC_ALL: nil
>  value of $LC_COLLATE: nil
>  value of $LC_CTYPE: nil
>  value of $LC_MESSAGES: nil
>  value of $LC_MONETARY: nil
>  value of $LC_NUMERIC: nil
>  value of $LC_TIME: nil
>  value of $LANG: en.UTF-8
>  value of $XMODIFIERS: nil
>  locale-coding-system: nil
>  default-enable-multibyte-characters: t
>
>
>
>
> 

bug#683: 23.0.60; Recursive load error stays

[Glenn Morris]

Markus Triska wrote:

> I have "~/p.el" which consists of the form:
>
>    (load "~/p.el")
>
> When I do:
>
>    emacs -Q ~/p.el
>
> and evaluate the form (C-x C-e), I get:
>
>    Debugger entered--Lisp error: (error "Recursive load"...
>
> as expected. Now I comment out the form:
>
>    ;(load "~/p.el")
>
> then save the file, and evaluate the form again. Now I again get:
>
>    Debugger entered--Lisp error: (error "Recursive load"...
>
> When I restart Emacs, it correctly evaluates the form.
>
>
> In GNU Emacs 23.0.60.1 (i386-apple-darwin8.11.1, GTK+ Version 2.12.9)


Do you still see this? It doesn't happen for me with the current CVS
on GNU/Linux.

bug#683: 23.0.60; Recursive load error stays

[Markus Triska]

Glenn Morris <rgm@gnu.org> writes:

> Do you still see this?

Yes - it works as I expect when I quit the debugger with "q", but not
within the recursive edit (i.e., if I leave the *Backtrace* buffer open
and do not exit the debugger). Other forms seem to evaluate as usual
also in the recursive editing level, whereas "load" seems different.

bug#683: 23.0.60; Recursive load error stays

[Juanma Barranquero]

On Tue, Aug 26, 2008 at 05:37, Markus Triska <markus.triska@gmx.at> wrote:

> Yes - it works as I expect when I quit the debugger with "q", but not
> within the recursive edit (i.e., if I leave the *Backtrace* buffer open
> and do not exit the debugger). Other forms seem to evaluate as usual
> also in the recursive editing level, whereas "load" seems different.

For starters, using C-x C-e inside a comment is a bit weird; it
"works", for single-line expressions, but it uses forward-sexp, whose
docstring says: "This command assumes point is not in a string or
comment."

That aside, what happens is this: `load' uses a static variable
Vloads_in_progress to detect recursive loads. On the normal (not
backtrace) case, *before reading the file*, it checks the name of the
file against Vloads_in_progress, finds nothing unusual, so it loads
the file (by calling the Vload_source_file_function).

In the backtrace case, when trying to load ~/p.el again, load is still
on the call stack, so Vloads_in_progress has not been reset to nil; as
expected, `load' finds p.el in Vloads_in_progress, and bails out. It
is irrelevant whether you commented out the line and saved the file,
because it is not being read yet at that point. If you try to load
another file instead you'll see it loads OK, because it is not in
Vloads_in_progress.

It is not a bug: calling a function when it is in the call stack will
be affected by global variables and other non-reentrant code used in
that function.

    Juanma