CaseInsensitiveDictionary

21class CaseInsensitiveDictionary implements ArrayAccess, IteratorAggregate {22	/**23	 * Actual item data24	 *25	 * @var array26	 */27	protected $data = [];28 29	/**30	 * Creates a case insensitive dictionary.31	 *32	 * @param array $data Dictionary/map to convert to case-insensitive33	 */34	public function __construct(array $data = []) {35		foreach ($data as $offset => $value) {36			$this->offsetSet($offset, $value);37		}38	}39 40	/**41	 * Check if the given item exists42	 *43	 * @param string $offset Item key44	 * @return boolean Does the item exist?45	 */46	#[ReturnTypeWillChange]47	public function offsetExists($offset) {48		if (is_string($offset)) {49			$offset = strtolower($offset);50		}51 52		if ($offset === null) {53			$offset = '';54		}55 56		return isset($this->data[$offset]);57	}58 59	/**60	 * Get the value for the item61	 *62	 * @param string $offset Item key63	 * @return string|null Item value (null if the item key doesn't exist)64	 */65	#[ReturnTypeWillChange]66	public function offsetGet($offset) {67		if (is_string($offset)) {68			$offset = strtolower($offset);69		}70 71		if ($offset === null) {72			$offset = '';73		}74 75		if (!isset($this->data[$offset])) {76			return null;77		}78 79		return $this->data[$offset];80	}81 82	/**83	 * Set the given item84	 *85	 * @param string $offset Item name86	 * @param string $value Item value87	 *88	 * @throws \WpOrg\Requests\Exception On attempting to use dictionary as list (`invalidset`)89	 */90	#[ReturnTypeWillChange]91	public function offsetSet($offset, $value) {92		if ($offset === null) {93			throw new Exception('Object is a dictionary, not a list', 'invalidset');94		}95 96		if (is_string($offset)) {97			$offset = strtolower($offset);98		}99 100		$this->data[$offset] = $value;