PHP7.0和php7.1中的语法新特性的总结

$param = $_GET['param'] ?? 1;

$param = isset($_GET['param']) ? $_GET['param'] : 1;

function add(int $a) { 
    return 1+$a; 
} 
var_dump(add(2);

function show(): array { 
    return [1,2,3,4]; 
}

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

// 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

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());

 echo "\u{9876}"

class Test {
    public $name = "lixuan";
}

//PHP7和PHP5.6都可以
$getNameFunc = function () {
    return $this->name;
};
$name = $getNameFunc->bindTo(new Test, 'Test');
echo $name();
//PHP7可以,PHP5.6报错
$getX = function () {
    return $this->name;
};
echo $getX->call(new Test);

//将所有对象分为__PHP_Incomplete_Class对象
$data = unserialize($foo, ["allowed_classes" => false]);
//将所有对象分为__PHP_Incomplete_Class 对象 除了ClassName1和ClassName2
$data = unserialize($foo, ["allowed_classes" => ["ClassName1", "ClassName2"]);
//默认行为，和 unserialize($foo)相同
$data = unserialize($foo, ["allowed_classes" => true]);

printf('%x', IntlChar::CODEPOINT_MAX);
echo IntlChar::charName('@');
var_dump(IntlChar::ispunct('!'));

ini_set('assert.exception', 1);
class CustomError extends AssertionError {}
assert(false, new CustomError('Some error message'));

//PHP7之前
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;

// PHP7之后
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};

var_dump(intp(7, 2));

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

function generator() {
    yield 1;
    yield 2;
    yield 3;
    return "a";
}

$generatorClass = ("generator")();
foreach ($generatorClass as $val) {
    echo $val ." ";

}
echo $generatorClass->getReturn();

function generator1() {
    yield 1;
    yield 2;
    yield from generator2();
    yield from generator3();
}

function generator2() {
    yield 3;
    yield 4;
}

function generator3() {
    yield 5;
    yield 6;
}

foreach (generator1() as $val) {
    echo $val, " ";
}

define('ANIMALS', ['dog', 'cat', 'bird']);
echo ANIMALS[1]; // outputs "cat"

function test(?string $name) {
    var_dump($name);
}

string(5) "tpunt"
NULL
Uncaught Error: Too few arguments to function test(), 0 passed in...

function swap(&$left, &$right) : void {
    if ($left === $right) {
        return;
    }
    $tmp = $left;
    $left = $right;
    $right = $tmp;
}
$a = 1;
$b = 2;
var_dump(swap($a, $b), $a, $b);

null
int(2)
int(1)

$data = [
    ['id' => 1, 'name' => 'Tom'],
    ['id' => 2, 'name' => 'Fred'],
];
while (['id' => $id, 'name' => $name] = $data) {
    // logic here with $id and $name
}

class ConstDemo
{
    const PUBLIC_CONST_A = 1;
    public const PUBLIC_CONST_B = 2;
    protected const PROTECTED_CONST = 3;
    private const PRIVATE_CONST = 4;
}

function iterator(iterable $iter) {
    foreach ($iter as $val) {
        //
    }
}

try {
    // some code
} catch (FirstException | SecondException $e) {
    // handle first and second exceptions
} catch (\Exception $e) {
    // ...
}

$data = [
    ['id' => 1, 'name' => 'Tom'],
    ['id' => 2, 'name' => 'Fred'],
];
while (list('id' => $id, 'name' => $name) = $data) {
    // logic here with $id and $name
}

var_dump("abcdef"[-2]);
var_dump(strpos("aabbcc", "b", -3));

string (1) "e"
int(3)

class Test {
    public function exposeFunction() {
        return Closure::fromCallable([$this, 'privateFunction']);
    }
    private function privateFunction($param) {
        var_dump($param);
    }
}
$privFunc = (new Test)->exposeFunction();
$privFunc('some value');

string(10) "some value"

pcntl_async_signals(true); // turn on async signals
pcntl_signal(SIGHUP,  function($sig) {
    echo "SIGHUP\n";
});
posix_kill(posix_getpid(), SIGHUP);

SIGHUP