/****************************************************************************
Prolog to Wam Compiler                     INRIA Rocquencourt - ChLoE Project
Version 2.1                                                Daniel Diaz - 1994

file : term.usr
****************************************************************************/
#include <string.h>

/*---------------------------------*/
/* Constants                       */
/*---------------------------------*/

#define ERR_COMPOUND_TERM_EXPECTED "\nError: compound term expected\n"
#define ERR_ARG_NB_INCORRECT       "\nError: arg nb must be in 1-arity\n"




/*---------------------------------*/
/* Type Definitions                */
/*---------------------------------*/

/*---------------------------------*/
/* Global Variables                */
/*---------------------------------*/

/*---------------------------------*/
/* Function Prototypes             */
/*---------------------------------*/

static 
Bool     Set_Arg                (void);






          /*---------------------------------------------------------------*/
          /* term_copy(T1,T2)                                              */
          /*                                                               */
          /* A(0) must be bound to a term                                  */
          /* A(1) will be unified with a copy of A(0)                      */
          /*---------------------------------------------------------------*/

#define Term_Copy_2                                                         \
    {                                                                       \
     int size;                                                              \
                                                                            \
     size=Term_Size(A(0));                                                  \
     Copy_Term(H,&A(0));                                                    \
     word=*H;                                                               \
     A(0)=Global_UnMove(Tag_Of(word)) ? Tag_Value(REF,H) : word;            \
     H+=size;                                                               \
     get_x_value(0,1)                                                       \
    }



          /*---------------------------------------------------------------*/
          /* setarg(ArgNb,T,V)                                             */
          /*                                                               */
          /* A(0) must be bound to an INT in 1..arity of T                 */
          /* A(1) must be bound to a compound term                         */
          /* A(2) must be bound to a Prolog term                           */
          /*---------------------------------------------------------------*/

#define Setarg_3                                                            \
     if (!Set_Arg())                                                        \
         fail




/* Above this line, put your first macros (these included by pragma_c) */

#undef  fail
#define fail Fail_Like_Bool

/* Below this line, put your others macros and your functions */




/*-------------------------------------------------------------------------*/
/* SET_ARG                                                                 */
/*                                                                         */
/*-------------------------------------------------------------------------*/
static Bool Set_Arg(void)

{
 WamWord  word,tag,*adr;
 AtomInf *functor;
 int      arity;
 WamWord *arg_adr;
 int      i;

 
 if ((functor=Get_Functor_Arity(A(1),&arity,&arg_adr))==NULL || arity==0)
    {
     Lib1(printf,ERR_COMPOUND_TERM_EXPECTED);
     return FALSE;
    }


 Deref(A(0),word,tag,adr)
 i=UnTag_INT(word);
 if (tag!=INT || (unsigned) i>arity)
    {
     Lib1(printf,ERR_ARG_NB_INCORRECT);
     return FALSE;
    }

 i--;

 Deref(A(2),word,tag,adr)
 Bind_OV((arg_adr+i),word)
}




/*-------------------------------------------------------------------------*/
/* INITIALIZE_USR                                                          */
/*                                                                         */
/*-------------------------------------------------------------------------*/
static void Initialize_Usr(void)

{
}



/* end of user file */

#undef  fail
#define fail Fail_Like_Wam