SWI-Prolog -- API-function PL_cons

Availability:C-language interface function

int PL_cons_functor(term_t -h, functor_t f, ...)

Create a term whose arguments are filled from a variable argument list holding the same number of term_t objects as the arity of the functor. To create the term animal(gnu, 50), use:

{ term_t a1 = PL_new_term_ref();
  term_t a2 = PL_new_term_ref();
  term_t t  = PL_new_term_ref();
  functor_t animal2;

  /* animal2 is a constant that may be bound to a global
     variable and re-used
  */
  animal2 = PL_new_functor(PL_new_atom("animal"), 2);

  PL_put_atom_chars(a1, "gnu");
  PL_put_integer(a2, 50);
  PL_cons_functor(t, animal2, a1, a2);
}

After this sequence, the term references a1 and a2 may be used for other purposes.