Re: [Chicken-users] How does Chicken know the # of arguments to a function

[Joel Reymont]

> felix winkelmann wrote:

>> But how does Chicken know how many arguments _to expect_?
>> 
>
>It's compiled into the code:
>
>(define (foo x y)
>  (print x y) )
>
>->
>
>/* foo in k18 in k15 in k12 */
>static void f_22(C_word c,C_word t0,C_word t1,C_word t2,C_word t3){
>C_word tmp;
>C_word t4;
>C_word *a;
>if(c!=4) C_bad_argc(c,4);           /*   <-- check (includes 2 implicit
>args) */

I was talking about the SWIG interface to Chicken where wrapper functions
are registered. I can't figure out where the number of arguments are
registered.

Each function pointer is added to a vector like this:

    {
        C_word *p0 = a;
        *(a++)=C_CLOSURE_TYPE|1;
        *(a++)=(C_word)_wrap_Container_clear;
        C_mutate(return_vec++, (C_word)p0);
    }

to be referred to like this:

(define SDL-EFSEEK (vector-ref swig-init-return 6))

    Joel

-- 
OpenPoker: The Linux of poker software
http://wagerlabs.com/forums
Tenerife: Canary Islands: Spain