PHP 7.x - past, present, future (WordPress Varna #4)

An overview of the cool new features in PHP 7, 7.1 and what's known for 7.2. Examples are WordPress related, as much as possible.

Presented at the local WordPress user group in Varna, Bulgaria.

Transcript

1. PHP 7.X - PAST, PRESENT, FUTURE
   Boyan Yordanov
   WordPress Varna Meetup #4
   

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2. ABOUT ME
   Developer at Shtrak
   Community fanboy
   Wannabe speaker and writer
   Organizer of phpVarna
   

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3. WHERE TO FIND ME?
   @specter_bg
   boyanyordanov
   boyanyordanov
   

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4. PHP 7 TIMELINE
   The Past: PHP 5.6 -> PHP 7.0
   The Present: PHP 7.0 -> PHP 7.1
   The Future: PHP Next (7.2)
   

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5. THE PAST
   

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6. DEATH OF PHP 5
   VERSION SUPPORT
   

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7. 5.6 IS PRACTICALLY ON LIFE SUPPORT
   AND PROJECTS ARE DROPPING IT
   The force is weak with those who think that “*” is a
   version constraint. twitter.com/tobySen/status…
   7:27 PM ­ 5 Feb 2017 · Oberding, Deutschland
   21 43
   Sebastian Bergmann
   @s_bergmann
   Follow
   Laravel 5.5 in July 2017 will require PHP 7+
   4:29 PM ­ 16 Dec 2016
   419 808
   Taylor Otwell
   @taylorotwell
   Follow
   #Symfony 4 (to released in November 2017) will drop
   #PHP 5 support... So, #Twig 2 stable should probably
   supports PHP 7 only, right?
   2:54 PM ­ 16 Dec 2016
   264 383
   Fabien Potencier
   @fabpot
   Follow
   For the future 2.6 release I will drop support for PHP <
   7.0 to massively simplify code. Should I keep support
   for PHP 5?
   1:22 PM ­ 13 Dec 2016 · City of London, London
   39 12
   Xdebug
   @xdebug
   Follow
   

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9. THE PRESENT
   

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10. PHP 7
    Worldwide celebration
    

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11. SUPPORT
    Ubuntu 16.04 and up
    Available via third parties on most Linux distros
    Available on the better shared and wp speci c
    providers: SiteGround, WP Engine, Bluehost,
    Superhosting, ICN
    WordPress.com runs PHP7
    

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12. FEATURES
    

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13. Speed and Memory consumption Benchmark
    (regular page)
    

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14. RSS feed
    Source: https://ma.ttias.be/wordpress-php-7-1/
    

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15. Abstract Syntax Trees (AST)
    

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16. Anonymous classes
    Cheap stubs
    $stub = new class implements SomeInterface{
    public function methodStub() {}
    };
    $subject = new ClassIamTesting($stub);
    

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17. Returning objects
    function objFromArray() {
    return (object) [
    'prop' => 'value';
    ];
    }
    // ...
    function objFromAnnonymous() {
    retrurn new class {
    public $prop = 'value';
    };
    }
    

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18. Return types
    Scalar type hints
    Throwable and Error
    and more
    declare(strict_types=1);
    function typesAreNotScary(int $number) : int {
    return $number;
    }
    

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19. MORE INFO
    Black re.io - optimizations added in PHP 7
    How Badoo saved one million dollars switching to
    PHP7
    

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20. PHP 7.1
    New stuff
    

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21. NULLABLE TYPES
    Previously
    function dummy(int $a) : int {
    return $a;
    }
    dummy(null); // TypeError
    

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22. NULLABLE TYPES
    Accepts null, but the argument is optional
    function dummy(int $a = null) : int {
    return $a ?? 0;
    }
    dummy(null); // returns 0
    dummy(); // still returns 0
    

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23. NULLABLE TYPES
    Now - allow null, but require int
    function dummy(?int $a) : ?int {
    return $a;
    }
    dummy(null); // returns null
    

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24. NULLABLE TYPES
    A more real use case
    function sum(?int $a, ?int $b) : int {
    $a = $a ?? 0;
    $b = $b ?? 0;
    return $a + $b;
    }
    ...
    // web request / console arguments
    $a = getFromInput('a');
    $b= getFromInput('b');
    $sum = sum($a, $b);
    

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25. function titlebox_shortcode($attrs = [], ?string $content, $tag =
    {
    // normalize attribute keys, lowercase
    $attrs = array_change_key_case((array)$attrs, CASE_LOWER);
    $title = $attrs['title'] ?? 'Default title';
    $content = $content ?? 'Default content';
    return "$title$content";
    }
    

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26. VOID RETURN TYPE
    function init_save() : void {
    add_action('save_post', 'my_custom_callback');
    }
    

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27. VOID RETURN TYPE
    function init_save() : void {
    // This will cause an Error
    return add_action('save_post', 'my_custom_callback');
    }
    

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28. VOID RETURN TYPE
    But you can still `return` to break execution
    function init_save() : void {
    if($someCondition) {
    return;
    }
    add_action('save_post', 'my_custom_callback');
    }
    

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29. ITERABLE PSEUDO-TYPE
    function iterateStruct(iterable $array) {
    foreach($array as $item) {
    // Do stuff with $item
    }
    }
    

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30. ITERABLE PSEUDO-TYPE
    Same result with any construct you can iterate over
    $array = ['item 1', 'item 2', 'item 3'];
    $collection = new class implements Iterator { ... };
    function gen() {
    yield 'item 1';
    yield 'item 2';
    yield 'item 3';
    }
    iterateStruct($array);
    iterateStruct($collection);
    iterateStruct(gen());
    

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31. LIST() AND ARRAY DESTRUCTURING CHANGES
    Use keys with list()
    Short syntax
    list('foo' => $foo, 'baz' =>$baz) = ['foo' => 1, 'bar' => 2];
    [$foo, $bar] = [1, 2, 3];
    ['foo' => $foo] = ['foo' => 1, 'bar' => 2];
    

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32. CLASS CONSTANT VISIBILITY
    Declare private, protected and public constants
    class SpecialConfig {
    private const MY_VALUE = 'value';
    public function doStuff() {
    echo self::MY_VALUE;
    }
    }
    $special = new SpecialConfig();
    $special­>doStuff(); // prints 'value'
    echo SpecialConfig::MY_VALUE; // throws error
    

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33. CATCHING MULTIPLE EXCEPTIONS
    try {
    // Do stuff and throw exception
    } catch (OneException | TwoException $e) {
    // add some common handling code
    }
    

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34. CATCHING MULTIPLE EXCEPTIONS
    Without the new thingy
    try {
    // Do stuff and throw exception
    } catch (OneException $e) {
    // do stuff with $e
    } catch (TwoException $e) {
    // copy­paste the same code from above
    }
    

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35. CLOSURE::FROMCALLABLE()
    Create closures from callable pseudo-type
    // Without the new method
    function filter_func() {}
    add_filter('example_filter', 'filter_func');
    // With the new syntax
    add_filter('example_filter', Closure::fromCallable('filter_func'));
    // Throws Error
    add_filter('example_filter', Closure::fromCallable('callback_wrong_name
    

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36. CLOSURE::FROMCALLABLE()
    You can use class methods too
    class FooPlugin () {
    public function init() {
    add_filter(
    'example_filter',
    Closure::fromCallable([$this, 'exampleFilterMethod']
    );
    }
    private function exampleFilterMethod() {}
    }
    (new FooPlugin)­>init();
    

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37. ARGUMENTCOUNTERROR
    NEGATIVE STRING OFFSETS
    function countsOnArguments($arg) {}
    countsOnArguments(); // throws ArgumentCountError
    $phpVarna = 'PHP Varna is cool.'
    echo $phpVarna[­5]; // prints "c"
    

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38. THE FUTURE
    

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39. PHP NEXT
    CURRENTLY PHP 7.2
    

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40. WHAT DO WE KNOW?
    No release date yet - probably in December again
    A bunch of things are deprecated
    New password hashing algorithm in core
    Libsodium will be in core
    

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41. LIBSODIUM
    From the RFC
    Libsodium is a modern cryptography library that offers
    authenticated encryption, high-speed elliptic curve
    cryptography, and much more. Unlike other cryptography
    standards (which are a potluck of cryptography primitives;
    i.e. WebCrypto), libsodium is comprised of carefully
    selected algorithms implemented by security experts to
    avoid side-channel vulnerabilities.
    

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42. ARGON2 HASHING ALGORITHM
    Uses PASSWORD_ARGON2I in password_* functions
    Control the parameters
    password_hash('password', PASSWORD_ARGON2I);
    passowrd_hash('password', PASSWORD_ARGON2I, [
    'memory_cost' => PASSWORD_ARGON2_DEFAULT_MEMORY_COST,
    'time_cost' => PASSWORD_ARGON2_DEFAULT_TIME_COST,
    'threads' => PASSWORD_ARGON2_DEFAULT_THREADS
    ]);
    

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43. PARAMETER TYPE WIDENING
    Skip type hints when overriding parent class methods
    class ArrayClass {
    public function foo(array $foo) { /* ... */ }
    }
    // This RFC proposes allowing the type
    // to be widened to be untyped aka any
    // type can be passed as the parameter.
    // Any type restrictions can be done
    // via user code in the method body.
    class EverythingClass extends ArrayClass {
    public function foo($foo) { /* ... */ }
    }
    

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44. COUNTING OF NON-COUNTABLE OBJECTS
    Any scalar, null or object not implementing Countable
    will raise a Warning
    CONVERT NUMERIC KEYS IN OBJECT/ARRAY CASTS
    Numeric keys are no longer lost in the conversion
    $obj = (object)['1' => 1, '2' => 2, '3' => 3];
    

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45. HOW TO STAY ON TOP?
    You don't have to
    

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46. NAVIGATING THE INTERNALS NEWS
    1. RFCs - the best source, sometimes abandoned or
    postponed a lot
    2. The mailing list - old, chaotic, hard to follow
    3. - internals mailing list in a nice UI
    4. Twitter:
    and many more, because the
    community is awesome!
    5. Blogs and
    6.
    Externals.io
    @of cial_php @nikita_ppv @SaraMG
    @DragonBe @CalEvans
    PHP Weekly newsletter
    PRs on PHP-SRC repo on GitHub
    

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47. QUESTIONS?
    THANK YOU!
    

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