Hy, Python & C play nicely with each other

fibs.c

#include "fibs.h"

long fib(int n)
{
  if (n == 0)
    return 1;
  else if (n == 1)
    return 1;
  else
    return fib(n-1) + fib(n-2);
}

fibs.h

#ifndef FIBS_H
#define FIBS_H

#include <stdio.h>

long fib(int n);

#endif

fibs.hy

(import [cffi [FFI]])

(def ffi (FFI))

(.cdef ffi "
   long fib(int n);
   ")

(defreader b [word] `(.encode ~word "UTF-8"))

(let [[kwargs {#b"sources" [#b"fibs.c"]
               #b"include_dirs" [#b"."]}]
      [lib (apply ffi.verify ["
    #include <fibs.h>
    #include <stdio.h>

    long fib(int n);"]
            kwargs)]]
  (print (.fib lib 40)))