Александр Трищенко: php 7 evolution

PHP 7 EVOLUTION

taken from https://wiki.php.net/phpng

Performance

taken from https://wiki.php.net/phpng

Performance

http://zsuraski.blogspot.com/2014/07/benchmarking-phpng.html

Performance

Removed deprecated functionality

Scalar types declaration

<?php// Coercive modefunction sumOfInts(int ...$ints) return array_sum($ints);

var_dump(sumOfInts(2, '3', 4.1));

//int(9)

Return type declarations

<?php

function arraysSum(array ...$arrays): array return array_map(function(array $array): int return array_sum($array); , $arrays);

print_r(arraysSum([1,2,3], [4,5,6], [7,8,9]));

/* Array ( [0] => 6 [1] => 15 [2] => 24 ) */

Strict mode isn't strict enough

http://tryshchenko.com/archives/47

Unlike parameter type declarations, the type

checking mode used for return types depends

on the file where the function is defined, not

where the function is called. This is because

returning the wrong type is a problem with the

callee, while passing the wrong type is a

problem with the caller.

Null coalesce operator

<?php// Fetches the value of $_GET['user'] and returns 'nobody' // if it does not exist.

$username = $_GET['user'] ?? 'nobody';

// This is equivalent to:

$username = isset($_GET['user']) ? $_GET['user'] : 'nobody';

// Coalesces can be chained: this will return the first // defined value out of $_GET['user'], $_POST['user'], and // 'nobody'.

$username = $_GET['user'] ?? $_POST['user'] ?? 'nobody';

Spaceship operator

<?php

// Integers

echo 1 <=> 1; // 0 echo 1 <=> 2; // -1 echo 2 <=> 1; // 1

// Floats

echo 1.5 <=> 1.5; // 0 echo 1.5 <=> 2.5; // -1 echo 2.5 <=> 1.5; // 1 // Strings

echo "a" <=> "a"; // 0 echo "a" <=> "b"; // -1 echo "b" <=> "a"; // 1

Constant arrays using define()

<?php define('ANIMALS', [ 'dog', 'cat', 'bird' ]);

echo ANIMALS[1]; // outputs "cat"

Group use declarations

use some\namespace\ClassA, ClassB, ClassC as C; use function some\namespace\fn_a, fn_b, fn_c; use const some\namespace\ConstA, ConstB, ConstC;

Generator Return Expressions

$gen = (function() yield 1; yield 2;

return 3; )();

foreach ($gen as $val) echo $val, PHP_EOL;

echo $gen->getReturn(), PHP_EOL;

//1 //2 //3

Generator delegation

function gen() yield 1; yield from gen2();

function gen2() yield 2; yield 3;

foreach (gen() as $val) echo $val, PHP_EOL; /* 1 23 */

Integer division with intdiv()

var_dump(intdiv(10, 3)); //3

PHP-NG

https://nikic.github.io/2015/05/05/Internal-value-representation-in-PHP-7-part-1.html

New zval structureHashTable size reduced from 72 to 56 bytesSwitch from dlmalloc to something similar to jemallocReduced MM overhead to 5%x64 support

Exceptions handling

interface Throwable |- Exception implements Throwable |- ... |- Error implements Throwable |- TypeError extends Error |- ParseError extends Error |- ArithmeticError extends Error |- DivisionByZeroError extends ArithmeticError |- AssertionError extends Error

https://trowski.com/2015/06/24/throwable-exceptions-and-errors-in-php7/

Exceptions handling

interface Throwable public function getMessage(): string; public function getCode(): int; public function getFile(): string; public function getLine(): int; public function getTrace(): array; public function getTraceAsString(): string; public function getPrevious(): Throwable; public function __toString(): string;

How to use it now

try // Code that may throw an Exception or Error. catch (Throwable $t)

// Executed only in PHP 7, will not match in PHP 5.x

catch (Exception $e)

// Executed only in PHP 5.x, will not be reached in PHP 7

Type errors

function add(int $left, int $right) return $left + $right;

try

$value = add('left', 'right');

catch (TypeError $e)

echo $e->getMessage();

// Argument 1 passed to add() must be of the type integer, string given

ParseError

try

require 'file-with-parse-error.php';

catch (ParseError $e)

echo $e->getMessage(), "\n";

//PHP Parse error: syntax error, unexpected ':', expecting ';' or ''

ArithmeticError

try

$value = 1 << ­1;

catch (ArithmeticError $e)

echo $e->getMessage(), "\n";

DivisionByZeroError

try

$value = 1 << ­1;

catch (DivisionByZeroError $e)

echo $e->getMessage(), "\n";

AssertionError

try

$value = 1 % 0;

catch (DivisionByZeroError $e)

echo $e->getMessage(), "\n";

//Fatal error: Uncaught AssertionError: assert($test === 0)

Applying function

//PHP5 WAY

PHP

<?phpclass TestClass protected $b = 'hello world';

//function ­ getter

$getB = function() return $this->b; //pay attention, context is undefined now! ;

$applied = $getB->bindTo(new TestClass, 'TestClass');

echo $applied();

Applying function

//PHP7 WAY

<?phpclass TestClass protected $b = 'hello world'; //function ­ getter $getB = function() return $this->b; //pay attention, context is undefined now! ; echo $getB->call(new TestClass);

Continue coming soon

Tryshchenko OleksandrDataart 2015

ensaierwa@gmail.comskype:ensaier