since 0.9.0
The system function "libmylib.so" •_FFI_ "userfunc" takes two strings as the path to the shared library and the name of the function you would like to extract, and returns a function that will call the function from the shared library.
This is a very thin wrapper around dlopen.
See man 3 dlopen for more documentation.
Example user function:
$ echo '
#include <cstdint>
#include <cstddef>
#include <iostream>
extern "C" double userfn(uint8_t nargs, void* args) {
std::cout << "Calling into CXBQN from FFI!\n";
return 0.0;
}
' >> userfn.cpp
$ mkdir build && cd build && cmake .. -DCXBQN_FFI=ON && make -j 12
$ g++ -fPIC -c -o userfn.o userfn.cpp
$ g++ -o userfn.so userfn.o
$ ./BQN -e '"tmp.so" •_FFI_ "userfn" @'
Calling into CXBQN from FFI!This FFI API will certainly change. Do not consider this stable. This functionality is just for playing around with the possibilities, not for any production use.