On Sun, 16 Aug 2009 17:43:04 +0100, Luís Oliveira wrote: > On Sun, Aug 16, 2009 at 5:14 PM, Tamas K Papp<tkp...@gmail.com> wrote: >> Is there a way to make mem-aref work with CL's complex numbers? I >> don't need anything else from CFFI (no complex function arguments, >> return types, etc), just mem-aref, eg something like >> >> (mem-aref ptr :complex-float 11) > > That is doable with something like: > > (defmethod translate-from-foreign (ptr (type complex-float-type)) > (complex (mem-aref ptr :float 0) (mem-aref ptr :float 1))) > > >> (setf (mem-aref ptr :complex-float 12) #C(1s0 2s0)) > > But that isn't. Would defining your own setter work for you? > > (defun complex-float-aref (ptr index c) > (let ((p (* (foreign-type-size :complex-float) index))) > (setf (mem-aref p :float 0) (realpart c) > (mem-aref p :float 1) (imagpart c)))) > > To do that with plain MEM-AREF as you wanted, I think we would need some > sort of TRANSLATE-INTO-FOREIGN hook.
Thanks for the quick reply. Yes, my own setter works, and I managed to prettify my code by writing a wrapper around mem-aref that calls the setter above when necessary. But if mem-ref and mem-aref could be extended to handle C99 complex types in the future, that would be neat (that means that my code would more more standard, and I would benefit from optimizations like compiler macros, etc). Tamas _______________________________________________ cffi-devel mailing list cffi-devel@common-lisp.net http://common-lisp.net/cgi-bin/mailman/listinfo/cffi-devel
