Check if current class has constant/enumeration based on value

php auto check enumerations

class Assets
{
	const ASSETS_BANNER = 'banner';
	const ASSETS_BLOG = 'blog';
	const ASSETS_TEMPLATE = 'template';

	private static $constants;

	public static function isConstant($value)
	{
		if (!isset(self::$constants))
		{
			$reflect = new ReflectionClass(__CLASS__);
			self::$constants = $reflect->getConstants();
			}
		return in_array($value, self::$constants);
	}
}