[cffi-devel] Re: unnamed callback (closures?)

[James Bielman]

Jan Rychter <jan at rychter.com> writes:

> I mostly develop on SBCL/x86 and ECL, so even if a solution worked
> on these platforms only, I'd be really happy.

If all else failed, you could resort to passing something like:

#+sbcl (alien-sap (alien-lambda ...))
#+ecl #| whatever is appropriate for an ecl anon callback |#

as a pointer to a CFFI function.

While I'd like to see some kind of CALLBACK-LAMBDA as the base
primitive in CFFI-SYS for callbacks someday, the implementation
support for this is pretty minimal.

I think it boils down to: how many Lisps need to support something
before we consider adding it an optional feature to CFFI-SYS?  If
there's enough support, what about exporting some sort of
CFFI-FEATURES:NO-ANONYMOUS-CALLBACKS feature and adding
CALLBACK-LAMBDA to CFFI-SYS for the Lisps that can do it?

James