[cffi-devel] Clisp load foreign library

[Luis Oliveira]

On 18/set/2005, at 03:39, Kenny Tilton wrote:
> I passed a pathname to load-foreign-library and Clisp complained that 
> it was not a string. Maybe I missed something. Anyway, if CLisp indeed 
> has a limitation in re accepting a pathname for a library, maybe the 
> CFFI wrapper could add that flexibility.

Yes, indeed. The details of CFFI-SYS:%LOAD-FOREIGN-LIBRARY are still 
very much undefined.

Now, about CFFI's handling of foreign libraries using CLISP, I'm not 
sure I understand what you want to do. Do you want to define bindings 
before loading the library, is that it?

When we get around to properly specify and extend load-foreign-library, 
one of the details in the documentation will be the requirement to load 
the foreign library before the bindings (and it would probably be nice 
to *enforce* this). So, you would have, say, bindings in fii.lisp and 
the calls to load-foreign-library in libraries.lisp, and libraries.lisp 
would have to be loaded before ffi.lisp. CMUCL requires this (UFFI has 
some notes about this too) and apparently so does CLISP (not because of 
its own FFI actually, but because of the way we do it in CFFI).

I say it would be nice to enforce stuff like this because we want the 
bindings to be portable, thus we want to try our best to avoid 
behaviour that will work on some lisps but not others. An example of 
that is UFFI's deref-array macro, in some lisps the type information is 
discarded so people testing with those won't notice they're passing 
wrong types etc... CFFI's has been avoiding this kind of behaviour 
pretty well I'd say.

The current cffi:load-foreign-library is a good example of what we 
don't want CFFI to be. :-) It'll be fixed.

-- 
Luís Oliveira
http://student.dei.uc.pt/~lmoliv/
Equipa Portuguesa do Translation Project
http://www.iro.umontreal.ca/translation/registry.cgi?team=pt