La evolución de PHP - 5.6 a 8.0 (Parte 1)

La traducción del artículo se preparó en previsión del inicio del curso  "Desarrollador backend en PHP" .

Hoja de trucos de cambios de PHP v7.x

PHP 7.3 PHP: .

, PHP PHP v7.x, - , , , - .

PHP 5.6 , . , , - .

PHP 7.0

:

new class($i) {
   public function __construct($i) {
       $this->i = $i;
   }
}

- ( 0).

. ( ) , EWARNING FALSE.

intdiv(int $numerator, int $divisor)

null - «??»

$x = NULL;
$y = NULL;
$z = 3;
vardump($x ?? $y ?? $z); // int(3)

$x = ["c" => "meaningfulvalue"];
vardump($x["a"] ?? $x["b"] ?? $x["c"]); // string(16) "meaningfulvalue"

- spaceship ( ) (<=>)

.

// 

f unction orderfunc($a, $b) {
   return ($a < $b) ? -1 : (($a > $b) ? 1 : 0);
}

//   <=>

function orderfunc($a, $b) {
   return $a <=> $b;
}

PHP - v0.5.

function add(float $a, float $b): float {
   return $a + $b;
}
add(1, 2); // float(3)

​​ - , . , ( v7.1 :))

interface A {
   static function make(): A;
}
class B implements A {
   static function make(): A {
       return new B();
   }
}

use

//  use :

use FooLibrary\Bar\Baz\ClassA;
use FooLibrary\Bar\Baz\ClassB;
use FooLibrary\Bar\Baz\ClassC;
use FooLibrary\Bar\Baz\ClassD as Fizbo;

//  use :
use FooLibrary\Bar\Baz{ ClassA, ClassB, ClassC, ClassD as Fizbo };

:

yield from <expr>

PHP 7 , PHP 5.6.

, PHP 7.0 . 7.0.0 3 , 5.6 opcache 2.7 opcache! !

Throwable

, , .

Error Exception Throwable.

Throwable:

interface Throwable
 |- Error implements Throwable
     |- ArithmeticError extends Error
         |- DivisionByZeroError extends ArithmeticError
     |- AssertionError extends Error
     |- ParseError extends Error
     |- TypeError extends Error
         |- ArgumentCountError extends TypeError
 |- Exception implements Throwable
     |- ClosedGeneratorException extends Exception
     |- DOMException extends Exception
     |- ErrorException extends Exception
     |- IntlException extends Exception
     |- LogicException extends Exception
         |- BadFunctionCallException extends LogicException
             |- BadMethodCallException extends BadFunctionCallException
         |- DomainException extends LogicException
         |- InvalidArgumentException extends LogicException
         |- LengthException extends LogicException
         |- OutOfRangeException extends LogicException
     |- PharException extends Exception
     |- ReflectionException extends Exception
     |- RuntimeException extends Exception
         |- OutOfBoundsException extends RuntimeException
         |- OverflowException extends RuntimeException
         |- PDOException extends RuntimeException
         |- RangeException extends RuntimeException
         |- UnderflowException extends RuntimeException
         |- UnexpectedValueException extends RuntimeException

⚠ ! Throwable Error Exception.

Unicode — “\u{xxxxx}”

echo "\u{202E}Reversed text"; //  ‮Reversed text

echo "mañana"; // "ma\u{00F1}ana"
echo "mañana"; // "man\u{0303}ana" "n"    ~ (U+0303)

-:

callable  class  trait  extends  implements  static  abstract  final  public  protected  private  const
enddeclare  endfor  endforeach  endif  endwhile  and  global  goto  instanceof  insteadof  interface
namespace  new  or  xor  try  use  var  exit  list  clone  include  includeonce  throw  array
print  echo  require  requireonce  return  else  elseif  default  break  continue  switch  yield
function  if  endswitch  finally  for  foreach  declare  case  do  while  as  catch  die  self parent

, - class - ::class.

return

dirname()

PHP 7.1

function answer(): ?int  {
   return null; // 
}

function answer(): ?int  {
   return 42; // 
}

function answer(): ?int {
   return new stdclass(); // 
}

function say(?string $msg) {
   if ($msg) {
       echo $msg;

   }

}

say('hello'); //  -  hello
say(null); //  -   
say(); //  -  
say(new stdclass); //  -   

function shouldreturnnothing(): void {
   return 1; // Fatal error: A void function must not return a value
}

, , , , .

void void , :

function lacksreturn(): void {
  // 
}

Iterable

array , Traversable, foreach. , array , Traversable - , , , .

function foo(iterable $iterable) {
   foreach ($iterable as $value) {
       // …
   }
}

iterable , , . Traversable, TypeError.

function bar(): iterable {
   return [1, 2, 3];
}

, iterable null .

function foo(iterable $iterable = []) {
   // …
}

Closure callable

class Closure {
   …
   public static function fromCallable(callable $callable) : Closure {…}
   …
}

$array = [1, 2, 3];

//  $a, $b  $c     $array  ,   
[$a, $b, $c] = $array;

//  $a, $b  $c    $array   "a", "b"  "c" 
["a" => $a, "b" => $b, "c" => $c] = $array;

list()

$powersOfTwo = [1 => 2, 2 => 4, 3 => 8];
list(1 => $oneBit, 2 => $twoBit, 3 => $threeBit) = $powersOfTwo;

class Token {
    //    public
   const PUBLICCONST = 0;

       //       
       private const PRIVATECONST = 0;
       protected const PROTECTEDCONST = 0;
       public const PUBLICCONSTTWO = 0;

      //        
       private const FOO = 1, BAR = 2;
}

try {
  // - …
} catch (ExceptionType1 | ExceptionType2 $e) {
 //   
} catch (\Exception $e) {
  // …
}

, .

:

• , ORM