primitive-load returning result of last evaluation?

primitive-load returning result of last evaluation?

[Andreas Rottmann]

Hi!

I wonder if it were possible to provide a primitive-load that returns
the result of the last expression evaluated. It would require just a
few-line-change in libguile/load.c and I guess it wouldn't break too
much since primitive-load returns SCM_UNSPECIFIED right now and one
can assume its return value isn't used (yet).

Regards, Andy
-- 
Andreas Rottmann         | Dru@ICQ        | 118634484@ICQ | a.rottmann@gmx.at
http://www.8ung.at/rotty | GnuPG Key: http://www.8ung.at/rotty/gpg.asc
Fingerprint              | DFB4 4EB4 78A4 5EEE 6219  F228 F92F CFC5 01FD 5B62

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Thien-Thi Nguyen]

   From: Andreas Rottmann <a.rottmann@gmx.at>
   Date: 09 Apr 2002 12:36:35 +0200

   I wonder if it were possible to provide a
   primitive-load that returns the result of the
   last expression evaluated. It would require
   just a few-line-change in libguile/load.c and I
   guess it wouldn't break too much since
   primitive-load returns SCM_UNSPECIFIED right
   now and one can assume its return value isn't
   used (yet).

i think this is a reasonable change, but perhaps
there is a good reason this hasn't been done since
return value was fixed in 1996-09 (libguile/load.c
1.4).

thi

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Rob Browning]

Thien-Thi Nguyen <ttn@giblet.glug.org> writes:

> i think this is a reasonable change, but perhaps there is a good
> reason this hasn't been done since return value was fixed in 1996-09
> (libguile/load.c 1.4).

I'd be hesitant to change this too until we've had a chance to
consider the issue carefully.  I can't think of anything offhand that
would make this a bad idea, but it's not functionality we could easily
rescind once we provide it, and I have this nagging feeling there
might be some problem I'm not thinking of...

-- 
Rob Browning
rlb @defaultvalue.org, @linuxdevel.com, and @debian.org
Previously @cs.utexas.edu
GPG=1C58 8B2C FB5E 3F64 EA5C  64AE 78FE E5FE F0CB A0AD

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Dirk Herrmann]

On Mon, 22 Apr 2002, Rob Browning wrote:

> Thien-Thi Nguyen <ttn@giblet.glug.org> writes:
> 
> > i think this is a reasonable change, but perhaps there is a good
> > reason this hasn't been done since return value was fixed in 1996-09
> > (libguile/load.c 1.4).
> 
> I'd be hesitant to change this too until we've had a chance to
> consider the issue carefully.  I can't think of anything offhand that
> would make this a bad idea, but it's not functionality we could easily
> rescind once we provide it, and I have this nagging feeling there
> might be some problem I'm not thinking of...

I can't think of any problems, except that the standard 'load itself does
not provide a return value.  And, implementing a load* that returns a
value is quite simple.  However, in order to spare people some work (I
once also needed such a load function), we should provide it, but, I'd
rather go for a standard implementation and provide such extensions as
optional packages.

Best regards
Dirk Herrmann


_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Rob Browning]

Dirk Herrmann <dirk@ida.ing.tu-bs.de> writes:

> I can't think of any problems, except that the standard 'load itself
> does not provide a return value.  And, implementing a load* that
> returns a value is quite simple.  However, in order to spare people
> some work (I once also needed such a load function), we should
> provide it, but, I'd rather go for a standard implementation and
> provide such extensions as optional packages.

So you'd like to see a separate function providing this feature
i.e. load-with-result and primitive-load-with-result (or whatever)?

-- 
Rob Browning
rlb @defaultvalue.org, @linuxdevel.com, and @debian.org
Previously @cs.utexas.edu
GPG=1C58 8B2C FB5E 3F64 EA5C  64AE 78FE E5FE F0CB A0AD

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Dirk Herrmann]

On Mon, 22 Apr 2002, Rob Browning wrote:

> Dirk Herrmann <dirk@ida.ing.tu-bs.de> writes:
> 
> > I can't think of any problems, except that the standard 'load itself
> > does not provide a return value.  And, implementing a load* that
> > returns a value is quite simple.  However, in order to spare people
> > some work (I once also needed such a load function), we should
> > provide it, but, I'd rather go for a standard implementation and
> > provide such extensions as optional packages.
> 
> So you'd like to see a separate function providing this feature
> i.e. load-with-result and primitive-load-with-result (or whatever)?

Yes, in a loadable module.  We could also make it the default and provide
the pure standard versions as an extension.  Both is possible.  Which way
we go depends on how people prefer to use guile:  1) Code in RnRS scheme
most of the time, being aware of using extensions, or 2) Code in
guile-extended scheme most of the time, only from time to time caring
about portability.

Personally, I prefer to have my code as portable as possible, but others
may think differently.  It's not worth to fight about it, but we should
think about which way we would like to go.  If we go for guile-extended
scheme, we should, however, have an easy way to start guile in an
as-strict-as-possible RnRS mode.

IMO, the best solution would be a minimum RnRS guile, including only
functionality for loading modules.  Even optional RnRS features should be
loaded on demand.  This way, so I hope, we could make guile's default size
very small, much smaller than today.

Best regards
Dirk Herrmann


_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Rob Browning]

Dirk Herrmann <dirk@ida.ing.tu-bs.de> writes:

> IMO, the best solution would be a minimum RnRS guile, including only
> functionality for loading modules.  Even optional RnRS features
> should be loaded on demand.  This way, so I hope, we could make
> guile's default size very small, much smaller than today.

FWIW I agree.

I think I'd probably rather see separately named functions for things
like "load returning value" than a redefinition of the functions when
you load a module.

-- 
Rob Browning
rlb @defaultvalue.org, @linuxdevel.com, and @debian.org
Previously @cs.utexas.edu
GPG=1C58 8B2C FB5E 3F64 EA5C  64AE 78FE E5FE F0CB A0AD

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel

Re: primitive-load returning result of last evaluation?

[Marius Vollmer]

Rob Browning <rlb@defaultvalue.org> writes:

> Thien-Thi Nguyen <ttn@giblet.glug.org> writes:
> 
> > i think this is a reasonable change, but perhaps there is a good
> > reason this hasn't been done since return value was fixed in 1996-09
> > (libguile/load.c 1.4).
> 
> I'd be hesitant to change this too until we've had a chance to
> consider the issue carefully.

Yes.  Before we make this change, we should have a way to put Guile
into a R5RS mode (maybe plus selected SRFIs).  The R5RS 'load' would
return #<unspecified>, while the normal Guile 'load' might return the
value of the last form, and take all kinds of additional arguments,
etc.

_______________________________________________
Guile-devel mailing list
Guile-devel@gnu.org
http://mail.gnu.org/mailman/listinfo/guile-devel