[PHP] 列挙型(Enum)の使い方

<?php
enum Color: int
{
  case RED = 1;
  case BLUE = 2;
  case GREEN = 3;

  public function label(): string
  {
    return match ($this) {
      self::RED => '赤',
      self::BLUE => '青',
      self::GREEN => '緑',
    };
  }

  public function katakanaLabel(): string
  {
    return match ($this) {
      self::RED => 'アカ',
      self::BLUE => 'アオ',
      self::GREEN => 'ミドリ',
    };
  }
}

<?php
require_once './Color.php';

foreach (Color::cases() as $color) {
  echo "<p>" . $color->value . ":" . $color->label() . ":" . $color->katakanaLabel() . "</p>";
}