Re: Accessing multiple values from C

[Mark H Weaver <mhw@netris.org>]

I think something along these lines be ideal,
though this code is UNTESTED.

     Mark


SCM
scm_c_value_ref (SCM obj, size_t idx)
{
  if (SCM_VALUESP (obj))
    {
      SCM values = scm_struct_ref (obj, SCM_INUM0);
      size_t i = idx;
      while (SCM_LIKELY (!scm_is_null (values)))
        {
          if (i == 0)
            return SCM_CAR (values);
          values = SCM_CDR (values);
          i--;
        }
    }
  else if (idx == 0)
    return obj;

  scm_error (scm_out_of_range_key,
	     "scm_c_value_ref",
	     "Too few values in ~S to access index ~S",
             scm_list_2 (obj, scm_from_unsigned_integer (idx)),
             scm_list_1 (scm_from_unsigned_integer (idx)));
}