Re: Is this statement correct?

Re: Is this statement correct?

[Sven Wischnowsky]

Andrej Borsenkow wrote:

> This from new section, User contribution/Utilities:
> 
> ====
> Recompiling Functions
> ---------------------
> 
> If you frequently edit your zsh functions, or periodically update your
> zsh installation to track the latest developments, you may find that
> function digests compiled with the zcompile builtin are frequently out
> of date with respect to the function source files.  This is not usually
> a problem, because zsh always looks for the newest file when loading a
> function, but it may cause slower shell startup and function loading.
> ====
> 
> I remember, that Sven explicitly stated that digest files are *not* checked
> against there source functions to save execution time (individual files are).
> I do not have articele number handy.

I vaguely remember having said something about this or something
similar but having been confused at that time (I don't remember when
that was either and can't offer a message number). However: yes, it is 
true. The code *does* compare the times for digest files, individual
zwc files and the original file (if they can be found). See the
function try_dump_file() in parse.c.

Bye
 Sven


--
Sven Wischnowsky                         wischnow@informatik.hu-berlin.de

RE: Is this statement correct?

[Andrej Borsenkow]

>
>
> Andrej Borsenkow wrote:
>
> > This from new section, User contribution/Utilities:
> >
> > ====
> > Recompiling Functions
> > ---------------------
> >
> > If you frequently edit your zsh functions, or periodically update your
> > zsh installation to track the latest developments, you may find that
> > function digests compiled with the zcompile builtin are frequently out
> > of date with respect to the function source files.  This is not usually
> > a problem, because zsh always looks for the newest file when loading a
> > function, but it may cause slower shell startup and function loading.
> > ====
> >
> > I remember, that Sven explicitly stated that digest files are
> *not* checked
> > against there source functions to save execution time (individual
> files are).
> > I do not have articele number handy.
>
> I vaguely remember having said something about this or something
> similar but having been confused at that time (I don't remember when
> that was either and can't offer a message number). However: yes, it is
> true. The code *does* compare the times for digest files, individual
> zwc files and the original file (if they can be found). See the
> function try_dump_file() in parse.c.
>


It does not work:

bor@itsrm2% print $fpath
/home/bor/.zsh.d/completion /home/bor/.zsh.d/std-3.1.9-dev-6.zwc
/home/bor/.zsh.d/functions /tools/share/zsh/site-functions ... (standard part
follows)
bor@itsrm2% ll /tools/share/zsh/3.1.9-dev-6/functions/Core/_match
-rw-r--r--   1 root     other       1539 Sep 19 09:44
/tools/share/zsh/3.1.9-dev-6/functions/Core/_match
bor@itsrm2% ll ~/.zsh.d/std-3.1.9-dev-6.zwc
-rw-------   1 bor      sinix    1491984 Sep 18 11:08
/home/bor/.zsh.d/std-3.1.9-dev-6.zwc

Zsh takes _match from digest file and *not* from external definition. Even if
it is newer.

-andrej

Re: Is this statement correct?

[Bart Schaefer]

On Sep 19,  9:50am, Andrej Borsenkow wrote:
} Subject: RE: Is this statement correct?
}
} > > This is not usually
} > > a problem, because zsh always looks for the newest file when loading a
} > > function, but it may cause slower shell startup and function loading.
} 
} It does not work:
} 
} bor@itsrm2% print $fpath
} /home/bor/.zsh.d/completion /home/bor/.zsh.d/std-3.1.9-dev-6.zwc
} /home/bor/.zsh.d/functions /tools/share/zsh/site-functions ... (standard
} part follows)
} bor@itsrm2% ll /tools/share/zsh/3.1.9-dev-6/functions/Core/_match
} -rw-r--r--   1 root     other       1539 Sep 19 09:44
} /tools/share/zsh/3.1.9-dev-6/functions/Core/_match
} bor@itsrm2% ll ~/.zsh.d/std-3.1.9-dev-6.zwc
} -rw-------   1 bor      sinix    1491984 Sep 18 11:08
} /home/bor/.zsh.d/std-3.1.9-dev-6.zwc
} 
} Zsh takes _match from digest file and *not* from external definition.
} Even if it is newer.

The order of $fpath takes precedence over the newness of the files.  It
doesn't search for the newest thing anywhere in $fpath; it checks for
the newest one of any two otherwise-equivalent sources of the function.

In particular, zsh does not read the name of the source file out of the
digest file and try to find it.  The autoload-time checks are all done
relative to *directories* named in $fpath.  If you put a digest name
into $fpath (as you have), then that file is accepted automatically.

If on the other hand you leave directory names in the path and put the
digest file alongside the directory (within that directory's parent),
then zsh will check for the newer of a function in the directory or a
function in the digest file.

So if you have fpath=(/zsh/fdir) and these three files:
    /zsh/fdir.zwc     /zsh/fdir/func     /zsh/fdir/func.zwc
Then zsh will always pick the newest one for the definition of "func".

I suppose the example in contrib.yo is a bit misleading because it
replaces the directory names with digest file names in $fpath.  That's
actually not necessary for zrecompile to work.

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

Zsh: http://www.zsh.org | PHPerl Project: http://phperl.sourceforge.net   

PATCH: RE: Is this statement correct?

[Andrej Borsenkow]

> 
> The order of $fpath takes precedence over the newness of the files.  It
> doesn't search for the newest thing anywhere in $fpath; it checks for
> the newest one of any two otherwise-equivalent sources of the function.
> 

If you agree with my english, I'll commit it to avoid more confusion.

-andrej

Index: Doc/Zsh/contrib.yo
===================================================================
RCS file: /cvsroot/zsh/zsh/Doc/Zsh/contrib.yo,v
retrieving revision 1.6
diff -u -r1.6 contrib.yo
--- Doc/Zsh/contrib.yo  2000/09/15 15:32:25     1.6
+++ Doc/Zsh/contrib.yo  2000/09/19 07:59:18
@@ -81,7 +81,9 @@
 digests compiled with the tt(zcompile) builtin are frequently out of date
 with respect to the function source files.  This is not usually a problem,
 because zsh always looks for the newest file when loading a function, but
-it may cause slower shell startup and function loading.
+it may cause slower shell startup and function loading. Also, if digest
+file is explicitly used as element of tt(fpath), zsh won't check if any
+of its source files was changed.
 
 The tt(zrecompile) autoloadable function, found in tt(Functions/Misc), can
 be used to keep function digests up to date.