Hi Stewart,

cl_object's are declared as :object type in ECL's ffi, so

(ffi:def-function "getObject" ((lo :pointer-void)) :returning :object) (ffi:def-function "setObject" ((lo :pointer-void) (clo :object)))

should work. CFFI does not support this as far as i know.

Hope that helps, Marius Gerbershagen

Am 29.07.2018 um 00:40 schrieb Stewart M.:

To clarify, the issue is not with C++, which I am successfully wrapping with C.

The actual issue is using the c_object type in Lisp--if it comes back as a CFFI pointer, how can I use it in Lisp as a Lisp object?  Is there something like:

(ffi:pointer-to-lisp-object ptr)

-- Stewart Milberger Kavalogic, Inc.

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On July 28, 2018 2:46 PM, Stewart M. sjm-mail@protonmail.com wrote:

...

I am using CFFI with ECL to interface to a C++ library, which has a C++ class with a data member of type 'cl_object'.  Simplified, my C++ code is:

class LispObject   {   public:     cl_object object;   };

extern "C" cl_object getObject(LispObject* lo) { return lo->object; }   extern "C" void setObject(LispObject* lo, cl_object clo) { lo->object = clo; }

The full code is:

https://common-lisp.net/viewvc/clive/trunk/src/extensions/corral/CliveCorral...

Can I somehow declare the 'cl_object' type for the 'getValue()' and 'setValue()' functions using CFFI 'defcfun' to get and set ECL objects?  Is there a technique using the lower-level FFI?  I am looking for a way to do this without compiling C code embedded in Lisp, which I am aware ECL can do.

Thank you for any ideas!

-- Stewart Milberger Kavalogic, Inc.