What's new in PHP 7.4?

Transcript

1. Zoeterenieweve
   rsiezientè?
   Oftewel: kiektekidoa,
   ‘t is PHP 7.4
   Jachim Coudenys
   @coudenysj
   https://jachim.be
   jachim.coudenys@combell.group
   

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3. Jachim
   Coudenys
   

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4. Deprecations &
   Removals
   

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5. Deprecations for PHP 7.4
   Functionality to be deprecated in PHP 7.4.
   https://wiki.php.net/rfc/deprecations_php_7_4
   

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6. Deprecations for PHP 7.4
   ● The real type
   ● Magic quotes legacy
   ● array_key_exists() with objects
   ● FILTER_SANITIZE_MAGIC_QUOTES filter
   ● Reflection export() methods
   ● mb_strrpos() with encoding as 3rd argument
   ● implode() parameter order mix
   ● Unbinding $this from non-static closures
   ● hebrevc() function
   ● convert_cyr_string() function
   ● money_format() function
   ● ezmlm_hash() function
   ● restore_include_path() function
   ● allow_url_include ini directive
   

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7. Deprecate alternate access to
   array elements and chars in string
   Deprecate curly braces array and string syntax access.
   https://wiki.php.net/rfc/deprecate_curly_braces_array_access
   

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8. Deprecate curly braces array
   $arr = [1, 2, 3];
   var_dump($arr{1});
   Deprecated: Array and string offset access syntax with curly braces is deprecated in test.php line 3
   int(2)
   https://3v4l.org/adbHI
   

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9. Deprecate left-associative ternary
   operator
   Deprecate nesting of ternaries without explicit use of parentheses.
   https://wiki.php.net/rfc/ternary_associativity
   

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10. Deprecate left-associative ternary operator
    return $a == 1 ? 'one'
    : $a == 2 ? 'two'
    : $a == 3 ? 'three'
    : $a == 4 ? 'four'
    : 'other';
    return $a == 1 ? 'one'
    : ($a == 2 ? 'two'
    : ($a == 3 ? 'three'
    : ($a == 4 ? 'four'
    : 'other')));
    return ((($a == 1 ? 'one'
    : $a == 2) ? 'two'
    : $a == 3) ? 'three'
    : $a == 4) ? 'four'
    : 'other';
    

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11. Deprecate left-associative ternary operator
    1 ? 2 : 3 ? 4 : 5; // deprecated
    (1 ? 2 : 3) ? 4 : 5; // ok
    1 ? 2 : (3 ? 4 : 5); // ok
    1 ?: 2 ? 3 : 4; // deprecated
    (1 ?: 2) ? 3 : 4; // ok
    1 ?: (2 ? 3 : 4); // ok
    1 ? 2 : 3 ?: 4; // deprecated
    (1 ? 2 : 3) ?: 4; // ok
    1 ? 2 : (3 ?: 4); // ok
    1 ?: 2 ?: 3; // ok
    (1 ?: 2) ?: 3; // ok
    1 ?: (2 ?: 3); // ok
    https://3v4l.org/H7ebn
    

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12. Deprecate and remove
    ext/interbase
    Deprecate and eventually remove the InterBase extension in the
    Core
    https://wiki.php.net/rfc/deprecate-and-remove-ext-interbase
    

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13. Unbundle ext/wddx
    https://wiki.php.net/rfc/deprecate-and-remove-ext-wddx
    

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14. WDDX
    WDDX (Web Distributed Data eXchange) is a programming language-, platform-
    and transport-neutral data interchange mechanism designed to pass data
    between different environments and different computers.
    https://en.wikipedia.org/wiki/WDDX
    

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15. Unbundle ext/recode
    https://wiki.php.net/rfc/unbundle_recode
    

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16. Recode
    This functionality is basically already supported by ext/iconv and ext/mbstring.
    While the two latter extensions rely on POSIX iconv support or libiconv, and the
    bundled libmbfl, respectively, ext/recode relies on the Recode library which is
    decomissioned and had its latest release on 22 January 2001.
    

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17. Improvements &
    New Features
    

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18. E_WARNING for invalid containers
    Raise E_WARNING for array access on invalid containers
    https://wiki.php.net/rfc/notice-for-non-valid-array-container
    

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19. E_WARNING for invalid containers
    $var = false;
    $var[1][2][3][4][5]; // This will throw a single E_WARNING, as accessing
    ($a[1])[2]
    // is attempting to access a IS_VAR chain that is NULL.
    // Output would be:
    // Warning: Variable of type boolean does not accept
    array offsets
    https://3v4l.org/QL5Gq
    

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20. E_WARNING for invalid containers
    $var = array(123);
    $var[0][1]; // This will throw an E_WARNING, as accessing $a[0] is
    valid
    // [1] is accessing an integer as an array.
    // Output would be:
    // Warning: Variable of type integer does not accept
    array offsets
    https://3v4l.org/v1E9J
    

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21. E_WARNING for invalid containers
    $a = [null];
    $c = null;
    var_dump($a[0][0] + $c[0]); // This will through 2 E_WARNINGS, First would
    be $a[0][0]
    // For the same reason as above, $a[0] is
    rightfully NULL
    // and accessing [0] on null is invalid. The
    second,
    // would be $c[0] for the same reason.
    // Output:
    // int(0)
    https://3v4l.org/V8qHp
    

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22. Base Convert improvements
    Changes to base convert to warn the user when incorrect values are
    passed. Also allow negative numbers to be parsed.
    https://wiki.php.net/rfc/base_convert_improvements
    

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23. Base Convert improvements
    The base_convert family of functions(base_convert, binhex, hexbin etc) are very
    accepting with their input arguments, you can pass any string to to them and they
    give a best effort of converting it.
    For example base_convert(“hello world”, 16, 10); will return 237 with no warnings.
    What this does internally is base_convert(“ed”, 16, 10); https://3v4l.org/3Jbem
    Also negative numbers simply do not work, eg base_convert(“-ff”, 16, 10); will
    return 255. (similar to above the “-” gets silently ignored). https://3v4l.org/nTaIL
    

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24. Base Convert improvements
    ● decbin() - Decimal to binary
    ● bindec() - Binary to decimal
    ● decoct() - Decimal to octal
    ● octdec() - Octal to decimal
    ● dechex() - Decimal to hexadecimal
    ● hexdec() - Hexadecimal to decimal
    

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25. Numeric Literal Separator
    Enable improved code readability by supporting an underscore
    between digits in numeric literals.
    https://wiki.php.net/rfc/numeric_literal_separator
    

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26. Numeric Literal Separator
    $threshold = 1_000_000_000; // a billion!
    var_dump($threshold);
    $discount = 135_00; // $135, stored as cents
    var_dump($discount);
    $testValue = 107_925_284.88; // scale is hundreds of
    millions
    var_dump($testValue);
    https://3v4l.org/mYEs5
    

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27. Allow throwing exceptions from
    __toString()
    Support throwing exceptions from __toString
    https://wiki.php.net/rfc/tostring_exceptions
    

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28. Null Coalesce Equal Operator
    Allow shorthand for self assigning null coalesce operator
    https://wiki.php.net/rfc/null_coalesce_equal_operator
    

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29. Null Coalesce Equal Operator
    // The folloving lines are doing the same
    $this->request->data['comments']['user_id'] =
    $this->request->data['comments']['user_id'] ?? 'value';
    // Instead of repeating variables with long names, the equal
    coalesce operator is used
    $this->request->data['comments']['user_id'] ??= 'value';
    

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30. mb_str_split() Split multibyte
    string
    https://wiki.php.net/rfc/mb_str_split
    

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31. Reflection for references
    Introduces the ReflectionReference class to allow detecting
    references and determining reference equality.
    https://wiki.php.net/rfc/reference_reflection
    

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32. New custom object serialization
    mechanism
    Introduces new custom object serialization mechanism to replace
    Serializable.
    https://wiki.php.net/rfc/custom_object_serialization
    

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33. New custom object serialization mechanism
    PHP currently provides two mechanisms for custom serialization of objects: The
    __sleep()/__wakeup() magic methods, as well as the Serializable interface.
    

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34. New custom object serialization mechanism
    The proposed serialization mechanism tries to combine the generality of
    Serializable with the implementation approach of __sleep()/__wakeup().
    Two new magic methods are added:
    // Returns array containing all the necessary state of the object.
    public function __serialize(): array;
    // Restores the object state from the given data array.
    public function __unserialize(array $data): void;
    

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35. Change the precedence of the
    concatenation operator
    Update the precedence of concatenation to be inferior to addition
    and subtraction
    https://wiki.php.net/rfc/concatenation_precedence
    

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36. Change the precedence of the concat operator
    echo "sum: " . $a + $b;
    // current behavior: evaluated left-to-right
    echo ("sum: " . $a) + $b;
    // desired behavior: addition and subtraction have a higher precendence
    echo "sum :" . ($a + $b);
    https://3v4l.org/i4pI7
    

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37. Types
    

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38. Covariant Returns and
    Contravariant Parameters
    https://wiki.php.net/rfc/covariant-returns-and-contravariant-parame
    ters
    

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39. Covariant Returns and Contravariant Parameters
    ● a parameter type can be substituted for one of its super-types
    ● a return type can substitute a sub-type.
    

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40. Covariant Returns and Contravariant Parameters
    interface A {
    function m(B $z);
    }
    interface B extends A {
    // permitted
    function m($z): A;
    }
    interface X {
    function m(Y $z): X;
    }
    interface Y extends X {
    // not permitted but type-safe
    function m(X $z): Y;
    }
    

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41. Typed Properties 2.0
    Add support for typed properties, including static properties and
    references to typed properties.
    https://wiki.php.net/rfc/typed_properties_v2
    

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42. Typed Properties
    class User {
    /** @var int $id */
    private $id;
    /** @var string $name */
    private $name;
    public function __construct(int $id, string $name) {
    $this->id = $id;
    $this->name = $name;
    }
    public function getId(): int {
    return $this->id;
    }
    public function setId(int $id): void {
    $this->id = $id;
    }
    public function getName(): string {
    return $this->name;
    }
    public function setName(string $name): void {
    $this->name = $name;
    }
    }
    

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43. Typed Properties
    class User {
    public int $id;
    public string $name;
    public function __construct(int $id, string $name) {
    $this->id = $id;
    $this->name = $name;
    }
    }
    

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44. Cool stuff!
    

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45. Spread Operator in Array
    Expression
    https://wiki.php.net/rfc/spread_operator_for_array
    

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46. Spread Operator in Array Expression
    $parts = ['apple', 'pear'];
    $fruits = ['banana', 'orange', ...$parts, 'watermelon'];
    // ['banana', 'orange', 'apple', 'pear', 'watermelon'];
    

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47. Arrow functions 2.0
    Adds short closures / arrow functions.
    https://wiki.php.net/rfc/arrow_functions_v2
    

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48. fn(parameter_list) => expr
    

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49. Arrow functions
    $extended = function ($c) use ($callable, $factory) {
    return $callable($factory($c), $c);
    };
    // with arrow function:
    $extended = fn($c) => $callable($factory($c), $c);
    

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50. Arrow functions
    $this->existingSchemaPaths = array_filter($paths, function ($v) use ($names) {
    return in_array($v, $names);
    });
    // with arrow function
    $this->existingSchemaPaths = array_filter($paths, fn($v) => in_array($v, $names));
    

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51. FFI - Foreign Function Interface
    https://wiki.php.net/rfc/ffi
    

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52. FFI - Foreign Function Interface
    // create FFI object, loading libc and exporting function printf()
    $ffi = FFI::cdef(
    "int printf(const char *format, ...);", // this is a regular C declaration
    "libc.so.6");
    // call C's printf()
    $ffi->printf("Hello %s!\n", "world");
    ?>
    

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53. Security
    

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54. Always available hash extension
    Proposes to make the hash extension available to every build of
    PHP.
    https://wiki.php.net/rfc/permanent_hash_ext
    

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55. Always available hash extension
    Make the hash extension (`ext/hash`) always available, similar to the `date`, `spl`
    & `pcre` extensions.
    

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56. Password Hash Registry
    Make the mechanisms used by password_hash/verify/etc…
    extensible by other modules.
    https://wiki.php.net/rfc/password_registry
    

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57. Password Hash Registry
    > print_r(password_algos());
    Array (
    [0] => "2y" // Ident for "bcrypt"
    [1] => "argon2i"
    [2] => "argon2id"
    )
    

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58. Argon2 support from sodium
    Provide password_hash
    https://wiki.php.net/rfc/sodium.argon.hash
    

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59. Improve
    openssl_random_pseudo_bytes()
    Proposes making openssl_random_pseudo_bytes
    https://wiki.php.net/rfc/improve-openssl-random-pseudo-bytes
    

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60. Improve openssl_random_pseudo_bytes()
    Throws exception instead of empty string/false on failure
    

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61. Escape PDO “?” parameter
    placeholder
    Changes to PDO to allow using operators containing “?” with
    pdo_pgsql, most commonly the JSON key exists “?” operator.
    https://wiki.php.net/rfc/pdo_escape_placeholders
    

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62. Escape PDO “?” parameter placeholder
    $stmt = $pdo->prepare('SELECT * FROM tbl WHERE json_col ?? ?');
    $stmt->execute(['foo']);
    SELECT * FROM tbl WHERE json_col ? 'foo'
    

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63. Performance &
    Garbage Collection
    

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64. weakrefs
    https://wiki.php.net/rfc/weakrefs
    

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65. weakrefs
    Weak references allow the programmer to retain a reference to an object which
    does not prevent the object from being destroyed. They are useful for
    implementing cache like structures.
    

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66. weakrefs
    WeakReference {
    public __construct ( void )
    public static create ( object $referent ) : WeakReference
    public get ( void ) : ?object
    }
    $obj = new stdClass;
    $weakref = WeakReference::create($obj);
    var_dump($weakref->get());
    unset($obj);
    var_dump($weakref->get());
    https://3v4l.org/hFqPp
    

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67. Preloading
    Preload PHP functions and classes once and use them in the
    context of any future request without overhead.
    https://wiki.php.net/rfc/preload
    

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68. OPCache on steroids
    

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69. OPCache
    ● Skips compiling step
    ● Still needs to link all classes on every request
    ○ Class inheritance
    ● Timestamp validation (optional)
    

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70. Preloading
    ● On server startup: compile and link everything in memory
    ○ Manual process via “preload file”
    ● Everything is available for all following requests
    ● Preloaded classes are now as fast as native function (strlen, \Exception, etc…)
    ● Server restart is needed to “refresh” code
    

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71. Preloading Config
    ● opcache.preload=/path/to/preload.php
    ● opcache_compile_file()
    

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72. Unlinked classes aren’t preloaded
    

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73. Preloading in the wild
    ● https://github.com/brendt/laravel-preload/blob/master/preload.php
    ● https://symfony.com/blog/new-in-symfony-4-4-preloading-symfony-applicatio
    ns-in-php-7-4
    // var/cache/dev/srcApp_KernelDevDebugContainer.preload.php
    // This file has been auto-generated by the Symfony Dependency Injection Component
    // You can reference it in the "opcache.preload" php.ini setting on PHP >= 7.4 when
    preloading is desired
    use Symfony\Component\DependencyInjection\Dumper\Preloader;
    require dirname(__DIR__, 3).'/vendor/autoload.php';
    require __DIR__.'/ContainerZxvZ783/srcApp_KernelDevDebugContainer.php';
    $classes = [];
    $classes[] = 'App\Kernel';
    Preloader::preload($classes);
    

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74. Caveats
    ● “Full server” (fpm)
    ○ php.ini setting
    ● Server restart
    

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75. Composer
    ● https://github.com/composer/composer/issues/7777#issuecomment-44026
    8416
    ● https://github.com/composer/composer/issues/7777
    You are welcome to keep the discussion going here as a central point for people interested in the topic
    to coordinate. But just to be clear, I am fairly confident that in the near future we are not going to add
    anything to Composer relating to preloading.
    If in a year it turns out - after people have been playing with it - that there is something Composer is
    uniquely positioned to really help with, we can revisit. For now it seems to me much more like an
    application/deployment concern than a dependency management one.
    

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77. Zotjes é?
    

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78. Upgrading / Migrating
    ● https://github.com/php/php-src/blob/PHP-7.4/UPGRADING
    ● https://www.php.net/manual/en/migration74.php
    

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79. http://phpversions.info/shared-hosting/
    

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80. Resources
    ● https://wiki.php.net/rfc#php_74
    ● https://symfony.com/blog/new-in-symfony-4-4-preloading-symfony-applicatio
    ns-in-php-7-4
    ● https://www.google.com/search?q=google+php+7.4
    

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81. Bedankté!
    https://joind.in/event/php-wvl-d
    ecember-meetup-at-bits-of-love/
    zoeterenieweversieziente
    Jachim Coudenys
    @coudenysj
    jachim.be
    

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