data.c

#include <string.h>
#include <ctype.h>
#include "npl.h"

//--------------list data type---------------------

int car(int addr)
{
    return (GET_CAR(addr));
}


int caar(int addr)
{
    return (car(car(addr)));
}


int cdar(int addr)
{
    return (cdr(car(addr)));
}


int cdr(int addr)
{
    return (GET_CDR(addr));
}


int cddr(int addr)
{
    return (cdr(cdr(addr)));
}


int cadr(int addr)
{
    return (car(cdr(addr)));
}


int caddr(int addr)
{
    return (car(cdr(cdr(addr))));
}


int cadddr(int addr)
{
    return (car(cdr(cdr(cdr(addr)))));
}


int caddddr(int addr)
{
    return (car(cdr(cdr(cdr(cdr(addr))))));
}


int cadddddr(int addr)
{
    return (car(cdr(cdr(cdr(cdr(cdr(addr)))))));
}


int cadar(int addr)
{
    return (car(cdr(car(addr))));
}


int cons(int car, int cdr)
{
    int addr;

    addr = freshcell();
    SET_TAG(addr, STRUCT);
    SET_CAR(addr, car);
    SET_CDR(addr, cdr);
    return (addr);
}



int wcons(int car, int cdr, int th)
{
    int addr;

    addr = wp[th];
    wp[th]++;
    if (wp[th] >= wp_max[th]) {
	exception(RESOURCE_ERR, NIL, makestr("wcons "), th);
    }
    SET_TAG(addr, STRUCT);
    SET_CAR(addr, car);
    SET_CDR(addr, cdr);
    SET_AUX(addr, 0);
    return (addr);
}

/*
bidirectional cons  bcons(x,y)
for record data base chain
	         (record1)   (record2)
               |          |
key-record ->(car,cdr)->(car,cdr)->....->NIL
	                  <- aux     <- aux 

	aux(addr) is previous cons
	cdr(addr) is next cons

*/
int bcons(int car, int cdr)
{
    int addr;

    addr = freshcell();
    SET_TAG(addr, STRUCT);
    SET_CAR(addr, car);
    SET_CDR(addr, cdr);
    SET_AUX(addr, 0);
    if (cdr != NIL)
	SET_AUX(cdr, addr);
    return (addr);
}


int assq(int sym, int lis)
{
    while (lis != NIL) {
	if (sym == caar(lis))
	    return (car(lis));
	lis = cdr(lis);
    }
    return (-1);
}



// assq1(foo,[foo/1,boo/2]) -> foo/1
int assq1(int sym, int lis)
{
    while (lis != NIL) {
	if (sym == cadr(car(lis)))
	    return (car(lis));
	lis = cdr(lis);
    }
    return (-1);
}



// replace([b,4],[[a,1][b,2][c,3]]) -> [[1,a],[b,4],[c,3]]
int replace(int x, int lis)
{
    int temp;

    temp = NIL;
    while (lis != NIL) {
	if (car(x) == caar(lis))
	    return (append(listreverse(temp), cons(x, cdr(lis))));

	temp = cons(car(lis), temp);
	lis = cdr(lis);
    }
    return (lis);
}



//if improper list return -1
int length(int addr)
{
    int len = 0;

    if (addr == NIL)
	return (0);

    while (!(nullp(addr))) {
	if (!structurep(addr))
	    return (-1);
	len++;
	addr = cdr(addr);
    }

    return (len);
}



int atom_length(int addr)
{
    char str[STRSIZE], c;
    int pos, n;

    strcpy(str, GET_NAME(addr));
    if (strlen(GET_NAME(addr)) == 2 && str[0] == '\\')
	return (1);

    pos = 0;
    n = 0;
    c = str[pos];
    while (c != NUL) {
	if (c == '\\') {
	    n++;
	    pos = pos + 2;
	} else if (isUni2(c)) {
	    n++;
	    pos = pos + 2;
	} else if (isUni3(c)) {
	    n++;
	    pos = pos + 3;
	} else if (isUni4(c)) {
	    n++;
	    pos = pos + 4;
	} else {
	    n++;
	    pos++;
	}
	c = str[pos];
    }
    return (n);
}



int string_length(int addr)
{
    char str[STRSIZE], c;
    int pos, n;

    strcpy(str, GET_NAME(addr));
    if (strlen(GET_NAME(addr)) == 2 && str[0] == '\\')
	return (1);

    pos = 0;
    n = 0;
    c = str[pos];
    while (c != NUL) {
	if (c == '\\') {
	    n++;
	    pos = pos + 2;
	} else if (isUni2(c)) {
	    n++;
	    pos = pos + 2;
	} else if (isUni3(c)) {
	    n++;
	    pos = pos + 3;
	} else if (isUni4(c)) {
	    n++;
	    pos = pos + 4;
	} else {
	    n++;
	    pos++;
	}
	c = str[pos];
    }
    return (n);
}


int list(int nest)
{
    if (nullp(nest))
	return (NIL);
    else
	return (cons(car(nest), list(cdr(nest))));
}


//append!
int append1(int x, int y)
{
    int z;

    if (nullp(x))
	return (y);
    z = x;
    while (!nullp(cdr(x))) {
	x = cdr(x);
    }
    SET_CDR(x, y);
    return (z);
}


int append(int x, int y)
{
    if (nullp(x))
	return (y);
    else
	return (listcons(car(x), append(cdr(x), y)));
}

int wappend(int x, int y, int th)
{
    if (nullp(x))
	return (y);
    else
	return (wlistcons(car(x), wappend(cdr(x), y, th), th));
}


int reverse(int x)
{
    int res;

    res = NIL;
    while (!(nullp(x))) {
	res = cons(car(x), res);
	x = cdr(x);
    }
    return (res);
}



int listreverse(int x)
{
    int res;

    res = NIL;
    while (!(nullp(x))) {
	res = cons(car(x), res);
	SET_AUX(res, LIST);
	x = cdr(x);
    }
    return (res);
}



int last(int x)
{
    return (car(listreverse(x)));
}

int improper_last(int x)
{
    if (singlep(x))
	return (x);
    else if (atomicp(x))
	return (x);
    else
	return (improper_last(cdr(x)));
}

int improper_butlast(int x)
{
    if (singlep(x))
	return (NIL);
    else if (atomicp(x))
	return (NIL);
    else
	return (listcons(car(x), improper_butlast(cdr(x))));
}


int addtail(int x, int y)
{
    return (listreverse(cons(x, (listreverse(y)))));
}


int list1(int x)
{
    return (cons(x, NIL));
}


int list2(int x, int y)
{
    return (cons(x, cons(y, NIL)));
}


int list3(int x1, int x2, int x3)
{
    return (cons(x1, cons(x2, cons(x3, NIL))));
}


int list4(int x1, int x2, int x3, int x4)
{
    return (cons(x1, cons(x2, cons(x3, cons(x4, NIL)))));
}


int list5(int x1, int x2, int x3, int x4, int x5)
{
    return (cons(x1, cons(x2, cons(x3, cons(x4, cons(x5, NIL))))));
}


int list6(int x1, int x2, int x3, int x4, int x5, int x6)
{
    return (cons
	    (x1, cons(x2, cons(x3, cons(x4, cons(x5, cons(x6, NIL)))))));
}


int list7(int x1, int x2, int x3, int x4, int x5, int x6, int x7)
{
    return (cons
	    (x1,
	     cons(x2,
		  cons(x3, cons(x4, cons(x5, cons(x6, cons(x7, NIL))))))));
}


int list8(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8)
{
    return (cons
	    (x1,
	     cons(x2,
		  cons(x3,
		       cons(x4,
			    cons(x5,
				 cons(x6, cons(x7, cons(x8, NIL)))))))));
}


int list9(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8,
	  int x9)
{
    return (cons
	    (x1,
	     cons(x2,
		  cons(x3,
		       cons(x4,
			    cons(x5,
				 cons(x6,
				      cons(x7,
					   cons(x8, cons(x9, NIL))))))))));
}



int list10(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8,
	   int x9, int x10)
{
    return (cons
	    (x1,
	     cons(x2,
		  cons(x3,
		       cons(x4,
			    cons(x5,
				 cons(x6,
				      cons(x7,
					   cons(x8,
						cons(x9,
						     cons(x10,
							  NIL)))))))))));
}


int wlist1(int x, int th)
{
    return (wcons(x, NIL, th));
}


int wlist2(int x, int y, int th)
{
    return (wcons(x, wcons(y, NIL, th), th));
}


int wlist3(int x1, int x2, int x3, int th)
{
    return (wcons(x1, wcons(x2, wcons(x3, NIL, th), th), th));
}


int wlist4(int x1, int x2, int x3, int x4, int th)
{
    return (wcons
	    (x1, wcons(x2, wcons(x3, wcons(x4, NIL, th), th), th), th));

}



int wlist5(int x1, int x2, int x3, int x4, int x5, int th)
{
    return (wcons
	    (x1,
	     wcons(x2, wcons(x3, wcons(x4, wcons(x5, NIL, th), th), th),
		   th), 0));
}



int wlist6(int x1, int x2, int x3, int x4, int x5, int x6, int th)
{
    return (wcons
	    (x1,
	     wcons(x2,
		   wcons(x3,
			 wcons(x4, wcons(x5, wcons(x6, NIL, th), th), th),
			 th), th), th));
}



int wlist7(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int th)
{
    return (wcons
	    (x1,
	     wcons(x2,
		   wcons(x3,
			 wcons(x4,
			       wcons(x5,
				     wcons(x6, wcons(x7, NIL, th), th),
				     th), th), th), th), th));

}



int wlist8(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8,
	   int th)
{
    return (wcons
	    (x1,
	     wcons(x2,
		   wcons(x3,
			 wcons(x4,
			       wcons(x5,
				     wcons(x6,
					   wcons(x7,
						 wcons(x8, NIL, th), th),
					   th), th), th), th), th), th));

}


int wlist9(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8,
	   int x9, int th)
{
    return (wcons
	    (x1,
	     wcons(x2,
		   wcons(x3,
			 wcons(x4,
			       wcons(x5,
				     wcons(x6,
					   wcons(x7,
						 wcons(x8,
						       wcons(x9,
							     NIL, th),
						       th), th), th),
				     th), th), th), th), th));
}



int wlist10(int x1, int x2, int x3, int x4, int x5, int x6, int x7, int x8,
	    int x9, int x10, int th)
{
    return (wcons
	    (x1,
	     wcons(x2,
		   wcons(x3,
			 wcons(x4,
			       wcons(x5,
				     wcons(x6,
					   wcons(x7,
						 wcons(x8,
						       wcons(x9,
							     wcons
							     (x10,
							      NIL, th),
							     th), th),
						 th), th), th), th), th),
		   th), th));
}



int nth(int addr, int n)
{
    while (!nullp(addr)) {
	if (n == 1)
	    return (car(addr));
	addr = cdr(addr);
	n--;
    }
    return (NIL);
}



//check data type
int constantp(int addr)
{
    if (integerp(addr))
	return (1);
    else if (!structurep(addr) && !variablep(addr))
	return (1);
    else
	return (0);
}



int atom_constant_p(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (GET_AUX(addr) == SIMP)
	return (1);
    else
	return (0);
}



// 'foo.pl' '123.23'
int atom_quote_p(int addr)
{
    int pos;
    char str[ATOMSIZE];

    if (IS_OUTCELL(addr))
	return (0);
    else if (operatorp(addr))
	return (0);
    else if (GET_AUX(addr) == SYS)
	return (0);
    else if (anonymousp(addr))
	return (0);
    else if (variablep(addr))
	return (0);
    else if (user_operator_p(addr))
	return (0);
    else if (singlep(addr)) {
	strcpy(str, GET_NAME(addr));
	if (str[0] == NUL)
	    return (1);
	if (isupper(str[0]))
	    return (1);
	if (isdigit(str[0]))
	    return (1);
	if (str[0] == '_' && GET_AUX(addr) == SIMP)
	    return (1);
	if (str[0] == '\'')
	    return (1);

	pos = 0;
	while (str[pos] != NUL) {
	    if (!(str[pos] == '_' || isalnum(str[pos])
		  || isUni2(str[pos])
		  || isUni3(str[pos]) || isUni4(str[pos])
		  || isUni5(str[pos]) || isUni6(str[pos]))
		|| str[pos] == ' ') {
		return (1);
	    }
	    if (isUni2(str[pos]))
		pos = pos + 2;
	    else if (isUni3(str[pos]))
		pos = pos + 3;
	    else if (isUni4(str[pos]))
		pos = pos + 4;
	    else if (isUni5(str[pos]))
		pos = pos + 5;
	    else if (isUni6(str[pos]))
		pos = pos + 6;
	    else
		pos++;
	}
	return (0);
    } else
	return (0);
}



int numberp(int addr)
{
    if (IS_ALPHA(addr))
	return (0);
    else if (integerp(addr))
	return (1);
    else if (IS_OUTCELL(addr))
	return (0);
    else if (IS_FLOAT(addr) || IS_LONGNUM(addr) || IS_BIGXNUM(addr))
	return (1);
    else
	return (0);
}



int integerp(int addr)
{
    if (IS_ALPHA(addr))
	return (0);
    else if (addr >= INT_FLAG)
	return (1);
    else if (addr < 0)
	return (1);
    else
	return (0);
}



int bignump(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_BIGXNUM(addr))
	return (1);
    else
	return (0);
}



int longnump(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_LONGNUM(addr))
	return (1);
    else
	return (0);
}



int wide_integer_p(int addr)
{
    if (integerp(addr) || longnump(addr) || bignump(addr))
	return (1);
    else
	return (0);
}



int floatp(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_FLOAT(addr))
	return (1);
    else
	return (0);
}



int stringp(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_STRING(addr))
	return (1);
    else
	return (0);
}



int atomp(int addr)
{
    if (nullp(addr))
	return (1);
    else if (singlep(addr) && !wide_variable_p(addr))
	return (1);
    else
	return (0);
}



int atomicp(int addr)
{
    if (atomp(addr))
	return (1);
    else if (numberp(addr))
	return (1);
    else
	return (0);
}



int characterp(int addr)
{
    if (atomp(addr) && atom_length(addr) == 1)
	return (1);
    else
	return (0);
}



int singlep(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_SINGLE(addr))
	return (1);
    else
	return (0);
}



int streamp(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_STREAM(addr))
	return (1);
    else
	return (0);

}


int structurep(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (IS_STRUCT(addr) || IS_NIL(addr))
	return (1);
    else
	return (0);
}


int socketp(int addr)
{
    if (streamp(addr) && GET_OPT(addr) == NPL_SOCKET)
	return (1);
    else
	return (0);
}


// [1,2,3] []
int listp(int addr)
{
    if (nullp(addr))
	return (1);
    else if (structurep(addr) && GET_AUX(addr) == LIST)
	return (1);
    else
	return (0);
}

// [L|Ls]
int pairp(int addr)
{
    if (listp(addr) && addr != NIL &&
	(compiler_variable_p(car(addr)) && compiler_variable_p(cdr(addr))))
	return (1);
    else
	return (0);
}

// (1,2,3).
int argumentsp(int addr)
{
    if (structurep(addr) &&
	car(addr) == AND &&
	(!structurep(cadr(addr)) ||
	 (operationp(cadr(addr)) && heavy999p(car(cadr(addr))))) &&
	(!structurep(caddr(addr)) ||
	 (operationp(caddr(addr)) && heavy999p(car(caddr(addr))))))
	return (1);
    else if (structurep(addr) &&
	     car(addr) == AND &&
	     (!structurep(cadr(addr)) ||
	      (structurep(cadr(addr)) && heavy999p(car(cadr(addr)))))
	     && argumentsp(caddr(addr)))
	return (1);
    else
	return (0);
}


int disjunctionp(int addr)
{
    if (structurep(addr) && IS_INCELL(car(addr)) && eqlp(car(addr), OR))
	return (1);
    else
	return (0);
}


int conjunctionp(int addr)
{
    if (structurep(addr) && IS_INCELL(car(addr)) && car(addr) == AND)
	return (1);
    else
	return (0);
}


int infix_operator_p(int addr)
{
    if (IS_OUTCELL(addr))
	return (0);
    else if (operatorp(addr) || notated_builtinp(addr)
	     || user_operator_p(addr))
	return (1);
    else
	return (0);
}


int infixp(int addr)
{
    if (structurep(addr) && infix_operator_p(car(addr)))
	return (1);
    else
	return (0);
}



int prefixp(int addr)
{
    int opt;

    if (structurep(addr) && infix_operator_p(car(addr)) &&
	((opt = GET_OPT(car(addr))) == FX || opt == FY))
	return (1);
    else
	return (0);
}



int postfixp(int addr)
{
    int opt;

    if (structurep(addr) && infix_operator_p(car(addr)) &&
	((opt = GET_OPT(car(addr))) == XF || opt == YF))
	return (1);
    else
	return (0);
}


int alphabeticalp(int addr)
{
    char *str;

    if (!singlep(addr))
	return (0);
    else {
	str = GET_NAME(addr);
	if (isalpha(*str))
	    return (1);
	else
	    return (0);
    }
}


int operatorp(int addr)
{
    if (singlep(addr) && GET_AUX(addr) == OPE)
	return (1);
    else
	return (0);
}


int user_operator_p(int addr)
{
    if (singlep(addr) && GET_AUX(addr) == USER)
	return (1);
    else
	return (0);

}


int user_operation_p(int addr)
{
    if (structurep(addr) && GET_AUX(addr) != LIST && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == USER)
	return (1);
    else
	return (0);
}



int notated_builtinp(int addr)
{
    int opt;

    if (singlep(addr) &&
	(GET_AUX(addr) == SYS || GET_AUX(addr) == OPE
	 || GET_AUX(addr) == COMP) &&
	((opt = GET_OPT(addr)) == XFX
	 ||
	 opt == YFX ||
	 opt == XFY
	 ||
	 opt == FX ||
	 opt == FY
	 ||
	 opt == XF ||
	 opt == YF
	 ||
	 opt == FX_XFX
	 ||
	 opt == FY_XFX
	 ||
	 opt == FX_XFY
	 ||
	 opt == FY_XFY
	 ||
	 opt == FX_YFX
	 ||
	 opt == FY_YFX
	 || opt == FX_XF || opt == FX_YF || opt == FY_XF || opt == FY_YF))
	return (1);
    else
	return (0);
}



int variablep(int addr)
{
    if (IS_ALPHA(addr))
	return (1);
    else if (singlep(addr) && GET_AUX(addr) == VAR)
	return (1);
    else
	return (0);
}

int variantp(int addr)
{
    if (IS_ALPHA(addr))
	return (1);
    else
	return (0);
}

int narrow_variable_p(int addr)
{
    char *var;

    if (singlep(addr) && GET_AUX(addr) == VAR) {
	var = GET_NAME(addr);
	if (var[0] == 'V' && var[1] == '_')
	    return (1);
	else
	    return (0);
    } else
	return (0);
}

// variable + anonymous_variable
int wide_variable_p(int addr)
{
    if (variablep(addr))
	return (1);
    else if (anonymousp(addr))
	return (1);
    else
	return (0);
}


int alpha_variable_p(int addr)
{
    if (IS_ALPHA(addr))
	return (1);
    else
	return (0);
}


int atom_variable_p(int addr)
{
    if (IS_INCELL(addr) && singlep(addr) && GET_AUX(addr) == VAR)
	return (1);
    else
	return (0);
}



int anonymousp(int addr)
{
    if (IS_INCELL(addr) && singlep(addr) && GET_AUX(addr) == ANOY)
	return (1);
    else
	return (0);
}



int predicatep(int addr)
{
    if (structurep(addr) && GET_AUX(addr) != LIST && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == PRED)
	return (1);
    else if (IS_INCELL(addr) && GET_AUX(addr) == PRED)
	return (1);
    else
	return (0);
}


int functionp(int addr)
{
    if (structurep(addr) && GET_AUX(addr) != LIST && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == FUNC)
	return (1);
    else if (IS_INCELL(addr) && GET_AUX(addr) == FUNC)
	return (1);
    else
	return (0);
}



int termp(int addr)
{
    if (structurep(addr) && GET_AUX(addr) != LIST && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == PRED)
	return (1);
    else
	return (0);
}


int atom_predicate_p(int addr)
{
    if (IS_INCELL(addr) && GET_AUX(addr) == PRED)
	return (1);
    else
	return (0);
}



int clausep(int addr)
{
    if (IS_INCELL(addr) && structurep(addr) && GET_AUX(addr) != LIST
	&& IS_INCELL(car(addr)) && car(addr) == NECK)
	return (1);
    else
	return (0);
}



int operationp(int addr)
{
    if (structurep(addr) && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == OPE && GET_AUX(addr) != LIST)
	return (1);
    else
	return (0);
}


// e.g. -1 -p
int single_operation_p(int addr)
{
    if (operationp(addr) && length(addr) == 2)
	return (1);
    else if (integerp(addr) && GET_INT(addr) < 0)
	return (1);
    else
	return (0);
}



int builtinp(int addr)
{
    if (structurep(addr) && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == SYS && GET_AUX(addr) != LIST)
	return (1);
    else if (IS_INCELL(addr) && GET_AUX(addr) == SYS)
	return (1);
    else
	return (0);
}


int compiledp(int addr)
{
    if (structurep(addr) && IS_INCELL(car(addr))
	&& GET_AUX(car(addr)) == COMP && GET_AUX(addr) != LIST)
	return (1);
    else if (IS_INCELL(addr) && GET_AUX(addr) == COMP)
	return (1);
    else
	return (0);
}


int compoundp(int addr)
{
    if (structurep(addr) && !IS_NIL(addr))
	return (1);
    else
	return (0);
}



int groundp(int addr)
{
    if (nullp(addr))
	return (1);
    else if (wide_variable_p(addr))
	return (0);
    else if (atomp(addr))
	return (1);
    else if (numberp(addr))
	return (1);
    else if (listp(addr))
	return (groundp(car(addr)) && groundp(cdr(addr)));
    else if (groundp(cadr(addr)) && groundp(caddr(addr)))
	return (1);
    else
	return (0);

    return (1);
}


int aliasp(int addr)
{
    if (IS_INCELL(addr) && singlep(addr) && IS_INCELL(car(addr))
	&& streamp(car(addr)))
	return (1);
    else
	return (0);
}



int has_variable_p(int addr)
{
    if (nullp(addr))
	return (0);
    else if (!structurep(addr))
	if (variablep(addr))
	    return (1);
	else
	    return (0);
    else if (has_variable_p(car(addr)) || has_variable_p(cdr(addr)))
	return (1);
    else
	return (0);
}



int has_value_p(int addr, int th)
{
    if (findvar(addr, th) == UNBIND)
	return (0);
    else
	return (1);
}



int has_no_value_p(int x, int th)
{
    while (!nullp(x)) {
	if (has_value_p(car(x), th))
	    return (0);
	x = cdr(x);
    }
    return (1);
}



int has_cut_p(int addr)
{
    if (addr == CUT)
	return (1);
    else if (!conjunctionp(addr))
	return (0);
    else if (conjunctionp(addr) && cadr(addr) == CUT)
	return (1);
    else
	return (has_cut_p(caddr(addr)));
}


int dcgp(int addr)
{
    if (structurep(addr) && car(addr) == DCG)
	return (1);
    else
	return (0);
}


// for parser. if weight of operator is heavy than 999
int heavy999p(int addr)
{
    if (GET_CDR(addr) % 10000 > 999 || GET_CDR(addr) / 10000 > 999)
	return (1);
    else
	return (0);
}


int callablep(int addr)
{
    if (variablep(addr))
	return (0);
    else if (numberp(addr))
	return (0);
    else if (atomp(addr))
	return (1);
    else if (predicatep(addr))
	return (1);
    else if (builtinp(addr))
	return (1);
    else if (compiledp(addr))
	return (1);
	else if (operationp(addr) && car(addr) == NECK){
		if (callablep(cadr(addr)) && callablep(caddr(addr)))
	    return (1);
		return(0);
	}
    else if (conjunctionp(addr)) {
	if (callablep(cadr(addr)) && callablep(caddr(addr)))
	    return (1);
	else
	    return (0);
    } else if (disjunctionp(addr)) {
	if (callablep(cadr(addr)) && callablep(caddr(addr)))
	    return (1);
	else
	    return (0);
    } else if (user_operation_p(addr))
	return (1);
    else
	return (0);
}



int mixturep(int addr)
{
    if (!singlep(addr))
	return (0);
    else if (GET_OPT(addr) == FX_XFX ||
	     GET_OPT(addr) == FX_XFY
	     ||
	     GET_OPT(addr) == FX_YFX ||
	     GET_OPT(addr) == FY_XFX
	     ||
	     GET_OPT(addr) == FY_XFY ||
	     GET_OPT(addr) == FY_YFX
	     ||
	     GET_OPT(addr) == FX_XF ||
	     GET_OPT(addr) == FX_YF
	     || GET_OPT(addr) == FY_XF || GET_OPT(addr) == FY_YF)
	return (1);
    else
	return (0);
}

int indicatorp(int addr)
{
    if (structurep(addr) && length(addr) == 3 && eqlp(car(addr), SLASH) &&
	(atomp(cadr(addr)) || variablep(cadr(addr))) &&
	(atomp(caddr(addr)) || variablep(caddr(addr))))
	return (1);
    else
	return (NO);
}


int get_1st_weight(int addr)
{
    return (GET_CDR(addr) / 10000);
}



int get_2nd_weight(int addr)
{
    return (GET_CDR(addr) % 10000);
}



int ifthenp(int addr)
{
    if (IS_INCELL(addr) && structurep(addr) && car(addr) == IFTHEN)
	return (1);
    else
	return (0);
}




int atom_codes_list_p(int addr)
{
    while (!nullp(addr)) {
	if (!integerp(car(addr)))
	    return (0);
	addr = cdr(addr);
    }
    return (1);
}



int nullp(int addr)
{
    if (IS_NIL(addr))
	return (1);
    else
	return (0);
}




int eqp(int addr1, int addr2)
{
    if (addr1 == addr2)
	return (1);
    else if (numberp(addr1) && numberp(addr2))
	if (numeqp(addr1, addr2))
	    return (1);
	else
	    return (0);
    else
	return (0);
}



// e.g. addr1 = makeatom("abc",SIMP); addr2 = makeatom("abc",SYS);
// then eqlp(addr1,addr2) = 1
int eqlp(int addr1, int addr2)
{
    if (addr1 == addr2)
	return (1);
    else if (atomp(addr1) && atomp(addr2)) {
	if (strcmp(GET_NAME(addr1), GET_NAME(addr2)) == 0)
	    return (1);
	else
	    return (0);
    } else if (numberp(addr1) && numberp(addr2)) {
	if (numeqp(addr1, addr2))
	    return (1);
	else
	    return (0);
    } else if (stringp(addr1) && stringp(addr2)) {
	if (strcmp(GET_NAME(addr1), GET_NAME(addr2)) == 0)
	    return (1);
	else
	    return (0);
    } else
	return (0);
}




int equalp(int addr1, int addr2)
{
    if (nullp(addr1) && nullp(addr2))
	return (1);
    else if (nullp(addr1) && !nullp(addr2))
	return (0);
    else if (!nullp(addr1) && nullp(addr2))
	return (0);
    else if (!structurep(addr1) && !structurep(addr2))
	return (eqlp(addr1, addr2));
    else if (!structurep(addr1) && structurep(addr2))
	return (0);
    else if (structurep(addr1) && !structurep(addr2))
	return (0);
    else if (equalp(car(addr1), car(addr2))
	     && equalp(cdr(addr1), cdr(addr2)))
	return (1);
    else
	return (0);

}



int streqp(int x, int y)
{
    if (strcmp(GET_NAME(x), GET_NAME(y)) == 0)
	return (1);
    else
	return (0);
}



int memq(int x, int y)
{
    while (!nullp(y)) {
	if (eqp(x, car(y)))
	    return (1);
	y = cdr(y);
    }

    return (0);
}



int memberp(int x, int y)
{
    while (!nullp(y)) {
	if (equalp(x, car(y)))
	    return (1);
	y = cdr(y);
    }
    return (0);
}




int listremove(int x, int y)
{
    if (nullp(y))
	return (NIL);
    else if (eqlp(x, car(y)))
	return (cdr(y));
    else
	return (cons(car(y), listremove(x, cdr(y))));
}



int remove_duplicate(int x)
{
    if (nullp(x))
	return (NIL);
    else if (memq(car(x), cdr(x)))
	return (remove_duplicate(cdr(x)));
    else
	return (listcons(car(x), remove_duplicate(cdr(x))));
}



/*
x1 is ignore
*/
int listremove3(int x1, int x2, int x3, int ls)
{
    if (nullp(ls))
	return (NIL);
    else if (equalp(x2, cadr(car(ls))) && equalp(x3, caddr(car(ls))))
	return (cdr(ls));
    else
	return (cons(car(ls), listremove3(x1, x2, x3, cdr(ls))));
}



int spypointp(int x)
{
    int atom, n, y;

    if (atomp(x)) {
	atom = x;
	n = 0;
    } else {
	atom = car(x);
	n = length(x) - 1;
    }
    y = list3(SLASH, atom, makeint(n));
    if (memberp(y, spy_list))
	return (1);
    else
	return (0);
}



int leappointp(int x)
{
    int atom, n, y;

    if (atomp(x)) {
	atom = x;
	n = 0;
    } else {
	atom = car(x);
	n = length(x) - 1;
    }
    y = list3(SLASH, atom, makeint(n));
    if (equalp(y, leap_point))
	return (1);
    else
	return (0);
}



int unique(int x)
{
    int res;

    res = NIL;
    while (!nullp(x)) {
	if (!memq(car(x), res))
	    res = cons(car(x), res);
	x = cdr(x);
    }
    return (res);
}


int unicodep(char c)
{
    if (isUni2(c) || isUni3(c) || isUni4(c) || isUni5(c) || isUni6(c))
	return (1);
    else
	return (0);
}



//-------for debug------------------
void cellprint(int addr)
{
    switch (GET_FLAG(addr)) {
    case FRE:
	printf("FRE ");
	break;
    case USE:
	printf("USE ");
	break;
    }
    switch (GET_TAG(addr)) {
    case EMP:
	printf("EMP    ");
	break;
    case INTN:
	printf("INTN   ");
	break;
    case FLTN:
	printf("FLTN   ");
	break;
    case SINGLE:
	printf("ATOM   ");
	break;
    case STRUCT:
	printf("STRUCT ");
	break;
    }
    printf("%07d ", GET_CAR(addr));
    printf("%07d ", GET_CDR(addr));
    printf("%07d ", GET_AUX(addr));
    printf("%s \n", GET_NAME(addr));
}



//dump heap
void heapdump(int start, int end)
{
    int i;

    printf("addr    F     TAG  CAR     CDR    BIND   NAME\n");
    for (i = start; i <= end; i++) {
	printf("%07d ", i);
	cellprint(i);
    }
}


//Prolog unification
int deref(int x, int th)
{
    int temp;

    if (nullp(x))
	return (NIL);
    else if (!structurep(x))
	return (deref1(x, th));
    else {
	temp = wcons(deref(car(x), th), deref(cdr(x), th), th);
	SET_AUX(temp, GET_AUX(x));
	return (temp);
    }
}



int deref1(int x, int th)
{

    int res;

    if (variablep(x)) {
      loop:
	res = findvar(x, th);
	if (res == UNBIND)
	    return (x);
	else if (variablep(res)) {
	    x = res;
	    goto loop;
	} else if (structurep(res))
	    return (deref(res, th));
	else
	    return (res);
    } else
	return (x);

    return (NIL);
}



int unify(int x, int y, int th)
{
    int x1, y1;

    if (nullp(x) && nullp(y))
	return (YES);
    else if (variablep(x) && !variablep(y)) {
	x1 = deref1(x, th);
	if (x1 == x) {
	    bindsym(x, y, th);
	    return (YES);
	} else
	    return (unify(x1, y, th));
    } else if (!variablep(x) && variablep(y)) {
	y1 = deref1(y, th);
	if (y1 == y) {
	    bindsym(y, x, th);
	    return (YES);
	} else
	    return (unify(x, y1, th));
    } else if (variablep(x) && variablep(y)) {
	x1 = deref1(x, th);
	y1 = deref1(y, th);
	if (variablep(x1) && variablep(y1)) {
	    if (x1 == y1 || x == y1 || x1 == y || x == y) {
		return (YES);
	    } else if (x != y) {	//ordinaly case
		bindsym(x1, y1, th);
		return (YES);
	    } else {
		bindsym(x1, makevariant(th), th);	// ex ?- X = X
		return (YES);
	    }
	} else if (variablep(x1) && !variablep(y1)) {
	    bindsym(x1, y1, th);
	    return (YES);
	} else if (!variablep(x1) && variablep(y1)) {
	    bindsym(y1, x1, th);
	    return (YES);
	} else {
	    return (unify(x1, y1, th));
	}
    } else if (anonymousp(x) || anonymousp(y)) {
	return (YES);
    } else if (constantp(x) && constantp(y)) {
	if (eqlp(x, y))
	    return (YES);
	else
	    return (NO);
    } else if (stringp(x) && stringp(y)) {
	if (streqp(x, y))
	    return (YES);
	else
	    return (NO);
    } else if (nullp(x) && !nullp(y))
	return (NO);
    else if (!nullp(x) && nullp(y))
	return (NO);
    else if (structurep(x) && !structurep(y))
	return (NO);
    else if (!structurep(x) && structurep(y))
	return (NO);
    else if (listp(x) && !listp(y))
	return (NO);
    else if (!listp(x) && listp(y))
	return (NO);
    else if (unify(car(x), car(y), th) == YES
	     && unify(cdr(x), cdr(y), th) == YES)
	return (YES);
    else
	return (NO);

    return (NO);
}



//typed unify. y is a pair list e.g. [L|Ls]
int unify_pair(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!listp(x))
	return (NO);
    else if (listp(x) && x != NIL && unify_var(car(x), car(y), th) == YES
	     && unify_var(cdr(x), cdr(y), th) == YES)
	return (YES);
    else
	return (NO);

    return (NO);
}


//typed unify. y is a small integer
int unify_int(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!integerp(x))
	return (NO);
    else if (eqp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}

//typed unify. y is a float
int unify_flt(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!floatp(x))
	return (NO);
    else if (numeqp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}


//typed unify. y is a long integer
int unify_long(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!longnump(x))
	return (NO);
    else if (numeqp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}

//typed unify. y is a long integer
int unify_big(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!bignump(x))
	return (NO);
    else if (bigx_eqp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}

//typed unify. y is an atom
int unify_atom(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!atomp(x))
	return (NO);
    else if (eqlp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}

//typed unify. y is a string
int unify_str(int x, int y, int th)
{
    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else if (!stringp(x))
	return (NO);
    else if (streqp(x, y))
	return (YES);
    else
	return (NO);

    return (NO);
}

//typed unify. y is a variable
int unify_var(int x, int y, int th)
{

    if (variablep(x)) {
	bindsym(x, y, th);
	return (YES);
    } else {
	bindsym(y, x, th);
	return (YES);
    }

    return (NO);
}


// typed unify. x is [] ?  (empty list)
int unify_nil(int x, int th)
{

    if (x == NIL)
	return (YES);
    else if (variablep(x)) {
	bindsym(x, NIL, th);
	return (YES);
    } else
	return (NO);

    return (NO);
}



//unbind to local-stack x
void unbind(int x, int th)
{
    int i;

    for (i = x; i < sp[th]; i++) {
	if (alpha_variable_p(stack[i][th])) {
	    variant[stack[i][th] - CELLSIZE][th] = UNBIND;
	} else if (atom_variable_p(stack[i][th])) {
	    if (alpha_variable_p(GET_CAR(stack[i][th]))) {
		variant[GET_CAR(stack[i][th]) - CELLSIZE][th] = UNBIND;
	    }
	    SET_CAR(stack[i][th], UNBIND);
	    SET_CDR(stack[i][th], UNBIND);
	} else
	    exception(SYSTEM_ERR, makestr("unbind"), x, th);
    }
    sp[th] = x;
}



// link variable and variant
void assign_variant(int x, int th)
{
    while (!nullp(x)) {
	SET_CDR(car(x), makevariant(th));
	x = cdr(x);
    }
}


// release link variable and variant
void release_variant(int x)
{
    while (!nullp(x)) {
	SET_CDR(car(x), NIL);
	x = cdr(x);
    }
}



int sort(int x)
{
    int res;

    res = NIL;
    while (!nullp(x)) {
	res = insert(res, (car(x)));
	x = cdr(x);
    }
    return (res);
}



int insert(int x, int y)
{
    if (nullp(x))
	return (listcons(y, NIL));
    else if (sortsmaller(y, car(x)))
	return (listcons(y, x));
    else if (sorteqlp(y, car(x)))
	return (x);
    else
	return (listcons(car(x), insert(cdr(x), y)));
}



int keysort(int x)
{
    int res;

    res = NIL;
    while (!nullp(x)) {
	res = keyinsert(res, (car(x)));
	x = cdr(x);
    }
    return (res);
}



int keyinsert(int x, int y)
{
    if (nullp(x))
	return (list1(y));
    else if (!(length(car(x)) == 3 && eqlp(caar(x), makeope("-"))))
	exception(ILLEGAL_ARGS, makeind("keysort", 2, 0), car(x), 0);
    else if (sortsmaller(cadr(y), cadr(car(x))))
	return (listcons(y, x));
    else
	return (listcons(car(x), keyinsert(cdr(x), y)));

    return (NIL);
}



int sortsmaller(int x, int y)
{
    if (variablep(x) && !variablep(y))
	return (1);
    else if (!variablep(x) && variablep(y))
	return (0);
    else if (variablep(x) && variablep(y)) {
	if (strcmp(GET_NAME(x), GET_NAME(y)) < 0)
	    return (1);
	else
	    return (0);
    } else
	return (atsmaller(x, y));
}



int sorteqlp(int x, int y)
{
    if (variablep(x) && !variablep(y))
	return (0);
    else if (!variablep(x) && variablep(y))
	return (0);
    else if (variablep(x) && variablep(y)) {
	if (strcmp(GET_NAME(x), GET_NAME(y)) == 0)
	    return (1);
	else
	    return (0);
    } else
	return (eqlp(x, y));
}



void printenv(int th)
{
    int i, j;

    for (j = 0; j < thread_num; j++) {
	for (i = 0; i < sp[j]; i++) {
	    if (alpha_variable_p(stack[i][th])) {
		print(stack[i][th]);
		printf("=");
		print(variant[stack[i][th] - CELLSIZE][j]);
	    } else if (atom_variable_p(stack[i][th])) {
		print(stack[i][th]);
		printf("=");
		print(GET_CAR(stack[i][th]));
	    }
	}
	printf("sp = %d", sp[j]);
    }
}



void add_data(int pred, int data)
{
    int clauses;

    //set arity. e.g. GET_CDR(pred) == #[2,3]
    memoize_arity(data, pred);
    clauses = GET_CAR(pred);
    if (nullp(clauses)) {
	SET_CAR(pred, cons(data, NIL));
    } else {
	while (!nullp(cdr(clauses))) {
	    clauses = cdr(clauses);
	}
	SET_CDR(clauses, cons(data, NIL));
    }
    if (!memq(pred, predicates))
	if (!module_flag && !dynamic_flag)
	    predicates = cons(pred, predicates);

}



void insert_data(int pred, int data)
{
    //set arity. e.g. GET_CDR(pred) == #[2,3]
    memoize_arity(data, pred);
    SET_CAR(pred, cons(data, GET_CAR(pred)));
    if (!memq(pred, predicates))
	if (!module_flag)
	    predicates = cons(pred, predicates);

}



/*
X -> call(X) e.g foo(X) :- X. -> foo(X) :- call(X).
atom without argument is converted to predicate
*/
int variable_to_call(int x)
{
    if (nullp(x))
	return (NIL);
    else if (variablep(x))
	return (list2(CALL, x));
    else if (atomp(x) && GET_AUX(x) == SIMP && !variablep(x) && x != FEND)
	return (makepred(GET_NAME(x)));
    else if (structurep(x) && (car(x) == AND || car(x) == OR))
	return (list3
		(car(x),
		 variable_to_call(cadr(x)), variable_to_call(caddr(x))));
    else if (structurep(x) && car(x) == NECK) {
	if (nullp(caddr(x)))	// e.g :- foo(x).
	    return (list2(car(x), cadr(x)));
	else			// normal case foo(X) :- bar(X).
	    return (list3(car(x), cadr(x), variable_to_call(caddr(x))));
    } else if (structurep(x) && car(x) == makeatom("-->", OPE))
	return (list3(car(x), cadr(x), variable_to_call(caddr(x))));
    else
	return (x);
}



int concat_atom(int x, int y)
{
    char str[ATOMSIZE];
    int res;

    strcpy(str, GET_NAME(x));
    strcat(str, "_");
    strcat(str, GET_NAME(y));
    res = makeatom(str, PRED);
    return (res);
}



int structure_to_list(int x)
{
    int res;

    x = listreverse(x);
    res = NIL;
    while (!nullp(x)) {
	res = listcons(car(x), res);
	x = cdr(x);
    }
    if (operatorp(car(res)))
	res = listcons(makeconst(GET_NAME(car(res))), cdr(res));

    return (res);
}



int list_to_structure(int x)
{
    int res;

    x = listreverse(x);
    res = NIL;
    while (!nullp(x)) {
	res = cons(car(x), res);
	x = cdr(x);
    }

    return (res);
}



int copy_term(int x)
{
    int temp;

    if (nullp(x))
	return (NIL);
    else if (variablep(x))
	return (x);
    else if (!structurep(x))
	return (x);
    else {
	temp = copy_term(car(x));
	return (cons(temp, copy_term(cdr(x))));
    }

    return (x);
}


int add_prefix1(int x)
{
    char str[STRSIZE];

    strcpy(str, GET_NAME(module_name));
    strcat(str, "_");
    strcat(str, GET_NAME(x));
    return (makepred(str));
}


int add_prefix(int x)
{
    if (structurep(x))
	return (cons(add_prefix1(car(x)), copy_heap(cdr(x))));
    else
	return (add_prefix1(x));
}

int exportp(int x)
{
    int i, name, arity;

    if (atomp(x)) {
	name = x;
	arity = 0;
    } else {
	name = car(x);
	arity = length(cdr(x));
    }


    for (i = 0; i < export_pt; i++) {
	if (eqlp(export_data[i][0], name) && export_data[i][1] == arity) {
	    return (1);
	}
    }
    return (0);
}

int copy_heap(int x)
{

    if (nullp(x))
	return (NIL);
    else if (IS_ALPHA(x))
	return (alpha_to_variable(x));
    else if (module_flag && predicatep(x) && exportp(x))
	return (x);
    else if (module_flag && predicatep(x) && !exportp(x))
	return (add_prefix(x));
    else if (singlep(x))
	return (x);
    else if (numberp(x))
	return (x);
    else if (stringp(x))
	return (x);
    else if (listp(x))
	return (listcons(copy_heap(car(x)), copy_heap(cdr(x))));
    else if (car(x) == NECK || car(x) == AND || car(x) == OR)
	return (list3(car(x), copy_heap(cadr(x)), copy_heap(caddr(x))));
    return (cons(copy_heap(car(x)), copy_heap(cdr(x))));
    return (x);
}


int copy_work(int x, int th)
{
    if (nullp(x))
	return (NIL);
    else if (IS_ALPHA(x))
	return (alpha_to_variable(x));
	else if (variablep(x))
	return (x);
    else if (singlep(x))
	return (x);
    else if (numberp(x))
	return (x);
    else if (stringp(x))
	return (x);
    else if (listp(x))
	return (wlistcons
		(copy_work(car(x), th), copy_work(cdr(x), th), th));
    else
	return (wcons(copy_work(car(x), th), copy_work(cdr(x), th), th));

    return (x);
}



// v_001(vairant) -> _v001(atom-variable)
int alpha_to_variable(int x)
{
    int res;
    char str[ATOMSIZE];

    sprintf(str, "_v%d", x - CELLSIZE);
    res = makeatom(str, VAR);
    return (res);
}



//transform from UTF-8 to unicode
int utf8_to_ucs4(char *p)
{
    int x, x1, x2, x3, res;
    unsigned char uc;

    uc = (unsigned char) *p;
    if (uc <= 0x7f) {
	x = (int) uc;
	return (x);
    } else if (uc >= 0xc0 && uc <= 0xdf) {
	x = (int) (UTF2MSK1 & uc);
	x = x << 6;
	p++;
	uc = (unsigned char) *p;
	x1 = (int) (UTFOMSKO & uc);
	res = x | x1;
	return (res);
    } else if (uc >= 0xe0 && uc <= 0xef) {
	x = (int) (UTF3MSK1 & uc);
	x = x << 12;
	p++;
	uc = (unsigned char) *p;
	x1 = (int) (UTFOMSKO & uc);
	x1 = x1 << 6;
	p++;
	uc = (unsigned char) *p;
	x2 = (int) (UTFOMSKO & uc);
	res = x | x1 | x2;
	return (res);
    } else if (uc >= 0xf0 && uc <= 0xf7) {
	x = (int) (UTF4MSK1 & uc);
	x = x << 18;
	p++;
	uc = (unsigned char) *p;
	x1 = (int) (UTFOMSKO & uc);
	x1 = x1 << 12;
	p++;
	uc = (unsigned char) *p;
	x2 = (int) (UTFOMSKO & uc);
	x2 = x2 << 6;
	p++;
	uc = (unsigned char) *p;
	x3 = (int) (UTFOMSKO & uc);
	res = x | x1 | x2 | x3;
	return (res);
    } else
	return (-1);
}



//transform from Unicode to UTF-8
void ucs4_to_utf8(int n, char *p)
{
    int w, x, y, z;

    if (n <= 0x7f) {
	*p = (char) n;
    } else if (n <= 0x07ff) {
	x = UNI2MSK1 & n;
	x = x >> 6;
	x = UNI2ADD1 | x;
	y = UNI2MSK2 & n;
	y = UNIOADDO | y;
	*p = (char) x;
	p++;
	*p = (char) y;
    } else if (n <= 0xffff) {
	x = UNI3MSK1 & n;
	x = x >> 12;
	x = UNI3ADD1 | x;
	y = UNI3MSK2 & n;
	y = y >> 6;
	y = UNIOADDO | y;
	z = UNI3MSK3 & n;
	z = UNIOADDO | z;
	*p = (char) x;
	p++;
	*p = (char) y;
	p++;
	*p = (char) z;
    } else if (n < 0x1fffff) {
	w = UNI4MSK1 & n;
	w = w >> 18;
	w = UNI4ADD1 | w;
	x = UNI4MSK2 & n;
	x = x >> 12;
	x = UNIOADDO | x;
	y = UNI4MSK3 & n;
	y = y >> 6;
	y = UNIOADDO | y;
	z = UNI4MSK4 & n;
	z = UNIOADDO | z;
	*p = (char) w;
	p++;
	*p = (char) x;
	p++;
	*p = (char) y;
	p++;
	*p = (char) z;
    } else {
	exception(SYSTEM_ERR, makestr("Unicode->UTF-8"), NIL, 0);
    }
    p++;
    *p = NUL;
}



int ctrl_to_number(char c)
{
    if (c == 'n')
	return (makeint(EOL));
    else if (c == 't')
	return (makeint(TAB));
    else if (c == 'f')
	return ((makeint(FF)));
    else if (c == 'r')
	return (makeint(CR));
    else if (c == 'v')
	return (makeint(VT));
    else if (c == 'a')
	return (makeint(BEL));
    else if (c == 'b')
	return (makeint(BS));
    else
	return (makeint(c));

    return (NIL);
}


int last_predicate(int x)
{
    if (!operationp(x))
	return (x);
    else
	return (last_predicate(caddr(x)));
}