char* lindex(int n) {
	char buf[BUFSIZ];
	sprintf(buf,"lindex %s %d",value(),n);
	return tk->evaluate( buf );
	}

int llength() {
	char buf[BUFSIZ];
	sprintf(buf,"llength %s",value());
	int n = 0; sscanf(tk->evaluate( buf ),"%d",&n);
	return n;
	}
