列挙型 - Wikipedia まず列挙型の定義は〜となるんだけど、ここでは「あらかじめ定義した値のいずれかしか取らない特殊な型」という感じを想定してます。 要はSplEnumみたいなのですが、拡張モジュールの力を借りなくても、PHPだけで作れます。リフレクションを使うだけ。 <?php abstract class Enum { private $scalar; public function __construct($value) { $ref = new ReflectionObject($this); $consts = $ref->getConstants(); if (! in_array($value, $consts, true)) { throw new InvalidArgumentException; } $this->scalar = $value; } final
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