PHP 7.0.x#

<?php
// Coercive mode
function sumOfInts(int ...$ints)
{
    return array_sum($ints);
}

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

int(9)

<?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
)

<?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';
?>

<?php
// 整数
echo 1 <=> 1; // 0
echo 1 <=> 2; // -1
echo 2 <=> 1; // 1

// 浮点数
echo 1.5 <=> 1.5; // 0
echo 1.5 <=> 2.5; // -1
echo 2.5 <=> 1.5; // 1

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

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

echo ANIMALS[1]; // 输出 "cat"
?>

<?php
interface Logger {
    public function log(string $msg);
}

class Application {
    private $logger;

    public function getLogger(): Logger {
         return $this->logger;
    }

    public function setLogger(Logger $logger) {
         $this->logger = $logger;
    }
}

$app = new Application;
$app->setLogger(new class implements Logger {
    public function log(string $msg) {
        echo $msg;
    }
});

var_dump($app->getLogger());
?>

object(class@anonymous)#2 (0) {
}

<?php
class A {private $x = 1;}

// PHP 7 之前版本的代码
$getXCB = function() {return $this->x;};
$getX = $getXCB->bindTo(new A, 'A'); // 中间层闭包
echo $getX();

// PHP 7+ 及更高版本的代码
$getX = function() {return $this->x;};
echo $getX->call(new A);

1
1

<?php

// 将所有的对象都转换为 __PHP_Incomplete_Class 对象
$data = unserialize($foo, ["allowed_classes" => false]);

// 将除 MyClass 和 MyClass2 之外的所有对象都转换为 __PHP_Incomplete_Class 对象
$data = unserialize($foo, ["allowed_classes" => ["MyClass", "MyClass2"]);

// 默认情况下所有的类都是可接受的，等同于省略第二个参数
$data = unserialize($foo, ["allowed_classes" => true]);

<?php

// PHP 7 之前的代码
use some\namespace\ClassA;
use some\namespace\ClassB;
use some\namespace\ClassC as C;

use function some\namespace\fn_a;
use function some\namespace\fn_b;
use function some\namespace\fn_c;

use const some\namespace\ConstA;
use const some\namespace\ConstB;
use const some\namespace\ConstC;

// PHP 7+ 及更高版本的代码
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};
?>

<?php

var_dump(intdiv(10, 3));
?>

int(3)

<?php
session_start([
    'cache_limiter' => 'private',
    'read_and_close' => true,
]);
?>

<?php
class foo {
    function foo() {
        echo 'I am the constructor';
    }
}
?>

Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; foo has a deprecated constructor in example.php on line 3

<?php
class foo {
    function bar() {
        echo 'I am not static!';
    }
}

foo::bar();
?>

Deprecated: Non-static method foo::bar() should not be called statically in - on line 8
I am not static!