function SCM_cons($s) { $x = $s->car; $y = $s->cdr->car; $cons = Cons::new_instance(); $cons->set_car($x); $cons->add_cdr($y); return $cons; }
/** * リスト評価 */ private static function evlis($args, $env) { $proc = $args; $cons = Cons::new_instance(); while ($proc) { $cons->add_cdr(self::evaluate($proc->car, $env)); $proc = $proc->cdr; } return $cons->cdr; }