NewPHP8.php

<?php

// NAMED ARGUMENTS
// PHP 7
htmlspecialchars($string, ENT_COMPAT | ENT_HTML401, 'UTF-8', false);

// PHP 8
htmlspecialchars($string, double_encode: false);

/****************************************/
// Constructor property promotion
// PHP 7
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;
  }
}

// PHP 8
class Point {
  public function __construct(
    public float $x = 0.0,
    public float $y = 0.0,
    public float $z = 0.0,
  ) {}
}

/****************************************/
// Match Expression
// PHP 7
switch (8.0) {
  case '8.0':
    $result = "Oh no!";
    break;
  case 8.0:
    $result = "This is what I expected";
    break;
}
echo $result;
//> Oh no!

// PHP 8
echo match (8.0) {
  '8.0' => "Oh no!",
  8.0 => "This is what I expected",
};
//> This is what I expected

/****************************************/
// UNION TYPES
// PHP 7
class Number {
  /** @var int|float */
  private $number;

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

new Number('NaN'); // Ok

// PHP 8
class Number {
  public function __construct(
    private int|float $number
  ) {}
}

new Number('NaN'); // TypeError