#include	"config.h"
#include	"mud.h"
#include	"u.h"
#include	"y.tab.h"


/* "cast" a node as a true/false value */
int
eval_castbool(n)
Nod	*n;
{
	if(n->rv.t == NUM && n->rv.iv != 0)
		return(1);
	if(n->rv.t == STR && n->rv.cv != (char *)0 && n->rv.cv[0] != '\0')
		return(1);
	if(n->rv.t == OID)
		return(cache_check(n->rv.cv));
	return(0);
}




/* "cast" a node as an int */
eval_castint(n)
Nod	*n;
{
	switch(n->rv.t) {
	case STR:
	case OID:
		return(atoi(n->rv.cv));
	case NUM:
		return(n->rv.iv);
	case VNULL:
		return(0);
	}
	return(0);
}




/* "cast" a node as a string */
char	*
eval_caststr(n)
Nod	*n;
{
	switch(n->rv.t) {
	case STR:
	case OID:
		return(n->rv.cv);
	case NUM:
		{
			char	nbuf[MAXOID];
			return(tmpstr(itoa(n->rv.iv,nbuf)));
		}
	case VNULL:
		return("NULL");
	}
	return("");
}



/* adopt a node's rv into our nval or rv */
void
eval_adopt(n1,n2,lrh)
Nod	*n1;
Nod	*n2;
int	lrh;
{
	if(lrh)
		n2->nv.t = n1->rv.t;
	else
		n2->rv.t = n1->rv.t;

	switch(n1->rv.t) {
		case STR:
		case OID:
			if(lrh)
				n2->nv.cv = n1->rv.cv;
			else
				n2->rv.cv = n1->rv.cv;
			break;
		case NUM:
		case VNULL:
			if(lrh)
				n2->nv.iv = n1->rv.iv;
			else
				n2->rv.iv = n1->rv.iv;
			break;

		/* some types (like subtrees) we don't assign to! */
		default:
			if(lrh) {
				n2->nv.t = VNULL;
				n2->nv.iv = UERR_ILLASGN;
			} else {
				n2->rv.t = VNULL;
				n2->rv.iv = UERR_ILLASGN;
			}

	}
}