#PHP 8 リリース新機能と変更

// php8新機能
array_fill(start_index: 0, num: 100, value: 50);

// php7
htmlspecialchars($string, ENT_COMPAT | ENT_HTML401, 'UTF-8', false);
// php8
htmlspecialchars($string, double_encode: false);

// php8新機能
<< WithoutArgument >>
<< SingleArgument （0 ）>>
<< FewArguments （'Hello' 、 'World' ）>>
function foo(){ }

// php7
class php7PostsController
{
    /**
     * @Route("/api/posts/{id}", methods={"GET"})
     */
    public function get($id) { /* ... */ }
}

// php8
class php8PostsController
{
    #[Route("/api/posts/{id}", methods: ["GET"])]
    public function get($id) { /* ... */ }
}

// php7
class Point {
  public float $x;
  public float $y;
  public float $z;

  public function __construct(
    float $x = 0.0,
    float $y = 0.0,
    float $z = 0.0,
  ) {
    $this->x = $x;
    $this->y = $y;
    $this->z = $z;
  }
}

//php8
class Point {
  public function __construct(
    public float $x = 0.0,
    public float $y = 0.0,
    public float $z = 0.0,
  ) {}
}

// php7
class Number {
  /** @var int|float */
  private $number;

  /**
   * @param float|int $number
   */
  public function __construct($number) {
    $this->number = $number;
  }
}

new Number('NaN'); // Ok

// php8
class Number {
  public function __construct(
    private int|float $number
  ) {}
}

new Number('NaN'); // TypeError

// php7
switch (8.0) {
  case '8.0':
    $result = "Oh no!";
    break;
  case 8.0:
    $result = "This is what I expected";
    break;
}
echo $result;
//> Oh no!

// php8
echo match (8.0) {
  '8.0' => "Oh no!",
  8.0 => "This is what I expected",
};
//> This is what I expected

// 新機能
echo match ($x) {
    1, 2 => 'Same for 1 and 2',
    3, 4 => 'Same for 3 and 4',
};

// php7
$country =  null;

if ($session !== null) {
  $user = $session->user;

  if ($user !== null) {
    $address = $user->getAddress();

    if ($address !== null) {
      $country = $address->country;
    }
  }
}

// php8
$country = $session?->user?->getAddress()?->country;

// bar()、baz()は実行されない
null?->foo(bar())->baz();

// php7
0 == 'foobar' // true

// php8
0 == 'foobar' // false

var_dump((int)"foo");   // int(0)
var_dump((int)""   );   // int(0)
var_dump((int)"42foo"); // int(42)