Re: Automatic stub generation?

[Klaus Schilling <Klaus.Schilling@home.ivm.de>]

Andrew Archibald writes:
 > Dirk Herrmann <dirk@ida.ing.tu-bs.de> writes:
 > 
 > > AFAIK there are two packages: SWIG and G-Wrap. Although I only use SWIG,
 > > some of the differences seem to be:
 > > 
 > > - SWIG supports interfaces for several scripting languages, not only for
 > >   guile. I contrast, G-Wrap generates only wrappers for scheme (maybe even
 > >   only for guile?)
 > > - SWIG has rudimentary (but for me sufficiently working) support for C++,
 > >   which doesn't seem to be true of G-Wrap. Maybe meanwhile wrappers for
 > >   C++ exist?
 > 
 > These are indeed true.  When I looked at it, though, SWIG didn't
 > support the current version of guile; it supported an obsolete
 > interface. 

Dav Beazley is currently in transition from utah to chicago. He finished school
and is now starting his new job. So this can take a big while.

 > 
 > > There are probably some aspects in favor of G-Wrap, but I especially
 > > remember these points, since they were crucial for me at the time I had to
 > > decide which packet to use.
 > 
 > There are.
 > 
 > G-Wrap is designed for guile, so it fits well.  Its author maintains
 > it for guile, and is interested in hearing comments.  It's designed so
 > a bcakend could be writen for any scheme which would allow your
 > application to use that scheme. 
 > 
Of course those backends don't come outta nothing, but need to be written by
people who know the C API of the individual scheme impl very well.

 > What made me choose it, though, was the way SWIG handles objects.
 > SWIG represents memory objects by hex-coded pointers stored in
 > strings.  I really don't trust this to interact with garbage
 > collection.  Perhaps SWIG can handle scheme now; but it couldn't when
 > I looked at it. 
 > 
That's just the exterior write representation of the objects.

 > > However, for GNOME I suggest considering SWIG, since ISTR that one of the
 > > GNOME issues is not to be fixed to a single language. If you are
 > > interested, I could send you some examples of how I usually wrap functions
 > > and data structures with SWIG.
 > 
 > The thing to do is wrap your spreadsheet as a library for easy
 > extensibility, so that it's easy to write a G-Wrap or SWIG description
 > file.  Personally, I'd use G-Wrap, and guile-gtk, and write my GUI in
 > guile.  

The question, on which level I should start to wrap C code to scheme subrs and
smobs, still causes me a lot of headache. Where is the line from where on one
should stop wrapping C code and starting with scheme? For example, for my
fullscreen charactercell user interfaces i've tried about anything from 
wrapping at the termcap/termios level and building a textwindowing system from
there in scheme to wrapping high-level textwidgets like Cdialog ...

In most cases wrapper tools are only of limited, temporary use. There is almost
always need of occasional manual intervention. 

Klaus Schilling