PHP could get better

PHP — . PHP, {lang_name} . - .

PHP . . . " — — — " .

PHP . , backend , . . . , .

. . , , . " " " ". , .

1.

. JavaScript .

let str = "1,2,3";

let arr = str.split(",");

arr = arr.map(_ => _ * 2);

console.log(arr); // [2, 4, 6]

, , , ..

JavaScript, , , . , String, .

PHP - ?

$str = '1,2,3';

$arr = $str->explode(',');

$arr = $arr->map(function ($i) {
    return $i * 2;
});

var_dump($arr);

//   :

$str = '1,2,3';

$arr = $str
    ->explode(',')
    ->map(function ($i) {
        return $i * 2;
    });

var_dump($arr);

, String Array. .

$arr->keyExists(...);
$arr->map(...);
$arr->filter(...);
$arr->keys(...);
$arr->push(...);
$arr->pop(...);
$arr->exists(...); // in_array

$str->repeat(...);
$str->join(...);
$str->trim(...);
$str->replace(...);

: . ? , is_iterable, is_numeric, is_countable, c instanceof \Countable, \Traversable .. ?

2.

, Java. . DI , , :

$service = $container->get<SomeService>();

, (Yii2 Query Doctrine).

, , type hinting ( ). , :

public function getItems(): Array<Item>

public function setItems(Array<Item>): void

, ? , , IDE , PHPDoc . , :

public function getItems(): Collection<Item>

public function setItems(Collection<Item>): void

PHPDoc (SomeObject[]), . , , ( array, ).

3.

Java 1.6 ( ). . (Java , , - )
JavaScript — ( , , Babel).
PHP? PHP PHPDoc , . , . , Doctrine PHP-DI.

, Symfony Event Dispatcher. -, , getSubscribedEvents, , — , — , . . , . ? . - , , -, getSubscribedEvents, (), () . , - , , . . , -, IDE ( — , IDE). .
, :

@EventSubscriber(ItemEvents::CREATE)
public function itemCreated(ItemEvent $event)

, . , , . . : - , , .

IDE, . , , namespace'.

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4. .

JavaScript (, ..) :

$input = [...];
$output = [];

foreach ($input as $i => $item) {
    // logic
    $output[$i] = $item;  
}

ReactJS + Redux :

let output = input.map(item => {
    // logic
    return item;
});

, PHP:

$output = array_map(function($item) {
    // logic
    return $item;
}, $input);

:

$output = $input->map(($item) => {
    // logic
    return $item;
});

, PHP -, function($item) {} - . , - ( JS). , . . RFC. , ?

5.

. JavaScript Promise. , .

PHP , , . HTTP . , , , . , Slack Mailgun . HTTP . , ? . .

PThreads, ? , , .

6.

:

class Money {
    __constuct($currency = new Currency('RUB')) {...}
}

:

class Money {
    private $currency = new Currency('RUB');

    public function setCurrency(Currency $currency) {...}
}

, , .

, , - , :

class Money {
    private $currency;

    __constuct(Currency $currency = null) {
        $this->currency = $currency ?? new Currency('RUB');
    }
}

. :

public function someMethod($value = $this->defaultValue): void

public $statuses = SomeClass::getStatuses();

.

7.

, (1) , (2) . , PHP . . , . , , PHP .

8. function

function .

public function someMethod()
// 
public someMethod()

. , PHP, Java JavaScript, . , ? . , , . , 9 , . , .

9.

, , . , PHP , , .. : , " ", . !
, , , ( Array::method()), deprecated. !

, PHP , , .. (json_encode -> Json::encode, cUrl).
- , , , , , Codesniffer … . , . , , .

, ( ) , . . , . . , PHP , .

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