rem: if (i) return(false); else return(true);
add: return (i ? false : true);
context: Cell *boolop(a,n) Node **a;{	register Cell *x, *y;	register int i;	x = execute(a[0]);	i = istrue(x);	tempfree(x, "");	switch (n) {	case BOR:		if (i) return(true);		y = execute(a[1]);		i = istrue(y);		tempfree(y, "");		if (i) return(true);		else return(false);	case AND:		if ( !i ) return(false);		y = execute(a[1]);		i = istrue(y);		tempfree(y, "");		if (i) return(true);		else return(false);	case NOT:		if (i) return(false);		else return(true);	default:	/* can't happen */		ERROR "unknown boolean operator %d", n FATAL;	}	/*NOTREACHED*/}