/****************************************************************************
* Writing out a bound variable *
****************************************************************************/
static void PRINT_writeBVar(WordPtr outStream, DF_TermPtr tmPtr)
{
int i;
int bvind = DF_bvIndex(tmPtr);
PRINT_BVList lbvs = PRINT_bvs;
for (i = bvind; ((i != 1) && lbvs) ; i--)
lbvs = lbvs->next;
// Is this checking and the else branch really necessary?
// Printing should start from top-level closed terms?
if (lbvs) STREAM_printf(outStream, "%s",
MCSTR_toCString(DF_strDataValue(lbvs->name)));
else STREAM_printf(outStream, "#%d", i);
}
/* (weak) head normalize bound variable or implicit suspension with
bound variable as term skeleton. */
static DF_TermPtr HN_hnormBV(DF_TermPtr bvPtr, Boolean whnf)
{
DF_TermPtr rtPtr; //term pointer to be returned
if (HN_isEmptyEnv()){ //[|#i, 0, 0, nil|] -> #i
rtPtr = bvPtr;
HNL_setRegsRig(bvPtr);
} else { //non-empty env
int dbind = DF_bvIndex(bvPtr);
if (dbind > ol) { //[|#i,ol,nl,e|] -> #i-ol+nl
int newind = dbind - ol + nl;
AM_embedError(newind);
rtPtr =(DF_TermPtr)AM_hreg;
HNL_pushBV(newind);
HNL_setRegsRig(rtPtr);
HN_setEmptyEnv();
} else { // i <= ol
DF_EnvPtr envitem = DF_envListNth(envlist, dbind);
int nladj = nl-DF_envIndex(envitem);
if (DF_isDummyEnv(envitem)){ //[|#i,ol,nl,..@l..|]->#(nl-l)
rtPtr = (DF_TermPtr)AM_hreg;
HNL_pushBV(nladj);
HNL_setRegsRig(rtPtr);
HN_setEmptyEnv();
} else { //pair env [|#i,ol,nl,..(s,l)..|] -> [|s,0,(nl-l),nil|]
DF_TermPtr tmPtr = DF_termDeref(DF_envPairTerm(envitem));
if ((nladj != 0) && (DF_isSusp(tmPtr))) {//combine susp
int newnl = DF_suspNL(tmPtr)+nladj;
AM_embedError(newnl);
HN_setEnv(DF_suspOL(tmPtr), newnl, DF_suspEnv(tmPtr));
rtPtr = HN_hnormDispatch(DF_suspTermSkel(tmPtr), whnf);
} else {
HN_setEnv(0, nladj, DF_EMPTY_ENV);
rtPtr = HN_hnormDispatch(tmPtr, whnf);
}
} //pair env
} // i<= ol
} //non-empty env
return rtPtr;
}
