PHP: PHP 8.4.0 Release Announcement

Released!

PHP 8.4 is a major update of the PHP language.
It contains many new features, such as property hooks, asymmetric visibility, an updated DOM API, performance improvements, bug fixes, and general cleanup.

Upgrade to PHP 8.4 now!

Property hooks RFC Doc

PHP < 8.4

class Locale
{
    private string $languageCode;
    private string $countryCode;

    public function __construct(string $languageCode, string $countryCode)
    {
        $this->setLanguageCode($languageCode);
        $this->setCountryCode($countryCode);
    }

    public function getLanguageCode(): string
    {
        return $this->languageCode;
    }

    public function setLanguageCode(string $languageCode): void
    {
        $this->languageCode = $languageCode;
    }

    public function getCountryCode(): string
    {
        return $this->countryCode;
    }

    public function setCountryCode(string $countryCode): void
    {
        $this->countryCode = strtoupper($countryCode);
    }

    public function setCombinedCode(string $combinedCode): void
    {
        [$languageCode, $countryCode] = explode('_', $combinedCode, 2);

        $this->setLanguageCode($languageCode);
        $this->setCountryCode($countryCode);
    }

    public function getCombinedCode(): string
    {
        return \sprintf("%s_%s", $this->languageCode, $this->countryCode);
    }
}

$brazilianPortuguese = new Locale('pt', 'br');
var_dump($brazilianPortuguese->getCountryCode()); // BR
var_dump($brazilianPortuguese->getCombinedCode()); // pt_BR

PHP 8.4

class Locale
{
    public string $languageCode;

    public string $countryCode
    {
        set (string $countryCode) {
            $this->countryCode = strtoupper($countryCode);
        }
    }

    public string $combinedCode
    {
        get => \sprintf("%s_%s", $this->languageCode, $this->countryCode);
        set (string $value) {
            [$this->countryCode, $this->languageCode] = explode('_', $value, 2);
        }
    }

    public function __construct(string $languageCode, string $countryCode)
    {
        $this->languageCode = $languageCode;
        $this->countryCode = $countryCode;
    }
}

$brazilianPortuguese = new Locale('pt', 'br');
var_dump($brazilianPortuguese->countryCode); // BR
var_dump($brazilianPortuguese->combinedCode); // pt_BR

Property hooks provide support for computed properties that can natively be understood by IDEs and static analysis tools, without needing to write docblock comments that might go out of sync. Furthermore, they allow reliable pre- or post-processing of values, without needing to check whether a matching getter or setter exists in the class.

Asymmetric Visibility RFC Doc

PHP < 8.4

class PhpVersion
{
    private string $version = '8.3';

    public function getVersion(): string
    {
        return $this->version;
    }

    public function increment(): void
    {
        [$major, $minor] = explode('.', $this->version);
        $minor++;
        $this->version = "{$major}.{$minor}";
    }
}

PHP 8.4

class PhpVersion
{
    public private(set) string $version = '8.4';

    public function increment(): void
    {
        [$major, $minor] = explode('.', $this->version);
        $minor++;
        $this->version = "{$major}.{$minor}";
    }
}

The scope to write to a property may now be controlled independently from the scope to read the property, reducing the need for boilerplate getter methods to expose a property’s value without allowing modification from the outside of a class.

`#[\Deprecated]` Attribute RFC Doc

PHP < 8.4

class PhpVersion
{
    /**
     * @deprecated 8.3 use PhpVersion::getVersion() instead
     */
    public function getPhpVersion(): string
    {
        return $this->getVersion();
    }

    public function getVersion(): string
    {
        return '8.3';
    }
}

$phpVersion = new PhpVersion();
// No indication that the method is deprecated.
echo $phpVersion->getPhpVersion();

PHP 8.4

class PhpVersion
{
    #[\Deprecated(
        message: "use PhpVersion::getVersion() instead",
        since: "8.4",
    )]
    public function getPhpVersion(): string
    {
        return $this->getVersion();
    }

    public function getVersion(): string
    {
        return '8.4';
    }
}

$phpVersion = new PhpVersion();
// Deprecated: Method PhpVersion::getPhpVersion() is deprecated since 8.4, use PhpVersion::getVersion() instead
echo $phpVersion->getPhpVersion();

The new #[\Deprecated] attribute makes PHP’s existing deprecation mechanism available to user-defined functions, methods, and class constants.

New ext-dom features and HTML5 support RFC RFC Doc

PHP < 8.4

$dom = new DOMDocument();
$dom->loadHTML(
    <<<'HTML'
        <main>
            <article>PHP 8.4 is a feature-rich release!</article>
            <article class="featured">PHP 8.4 adds new DOM classes that are spec-compliant, keeping the old ones for compatibility.</article>
        </main>
        HTML,
    LIBXML_NOERROR,
);

$xpath = new DOMXPath($dom);
$node = $xpath->query(".//main/article[not(following-sibling::*)]")[0];
$classes = explode(" ", $node->className); // Simplified
var_dump(in_array("featured", $classes)); // bool(true)

PHP 8.4

$dom = Dom\HTMLDocument::createFromString(
    <<<HTML
        <main>
            <article>PHP 8.4 is a feature-rich release!</article>
            <article class="featured">PHP 8.4 adds new DOM classes that are spec-compliant, keeping the old ones for compatibility.</article>
        </main>
        HTML,
    LIBXML_NOERROR,
);

$node = $dom->querySelector('main > article:last-child');
var_dump($node->classList->contains("featured")); // bool(true)

New DOM API that includes standards-compliant support for parsing HTML5 documents, fixes several long-standing compliance bugs in the behavior of the DOM functionality, and adds several functions to make working with documents more convenient.

The new DOM API is available within the Dom namespace. Documents using the new DOM API can be created using the Dom\HTMLDocument and Dom\XMLDocument classes.

Object API for BCMath RFC

PHP < 8.4

$num1 = '0.12345';
$num2 = 2;
$result = bcadd($num1, $num2, 5);

echo $result; // '2.12345'
var_dump(bccomp($num1, $num2) > 0); // false

PHP 8.4

use BcMath\Number;

$num1 = new Number('0.12345');
$num2 = new Number('2');
$result = $num1 + $num2;

echo $result; // '2.12345'
var_dump($num1 > $num2); // false

New BcMath\Number object enables object-oriented usage and standard mathematical operators when working with arbitrary precision numbers.

These objects are immutable and implement the Stringable interface, so they can be used in string contexts like echo $num.

New `array_*()` functions RFC

PHP < 8.4

$animal = null;
foreach (['dog', 'cat', 'cow', 'duck', 'goose'] as $value) {
    if (str_starts_with($value, 'c')) {
        $animal = $value;
        break;
    }
}

var_dump($animal); // string(3) "cat"

PHP 8.4

$animal = array_find(
    ['dog', 'cat', 'cow', 'duck', 'goose'],
    static fn (string $value): bool => str_starts_with($value, 'c'),
);

var_dump($animal); // string(3) "cat"

New functions array_find(), array_find_key(), array_any(), and array_all() are available.

PDO Driver specific SQL parsers RFC

PHP < 8.4

$connection = new PDO(
    'sqlite:foo.db',
    $username,
    $password,
); // object(PDO)

$connection->sqliteCreateFunction(
    'prepend_php',
    static fn ($string) => "PHP {$string}",
);

$connection->query('SELECT prepend_php(version) FROM php');

PHP 8.4

$connection = PDO::connect(
    'sqlite:foo.db',
    $username,
    $password,
); // object(Pdo\Sqlite)

$connection->createFunction(
    'prepend_php',
    static fn ($string) => "PHP {$string}",
); // Does not exist on a mismatching driver.

$connection->query('SELECT prepend_php(version) FROM php');

New subclasses Pdo\Dblib, Pdo\Firebird, Pdo\MySql, Pdo\Odbc, and Pdo\Sqlite of PDO are available.

`new MyClass()->method()` without parentheses RFC Doc

PHP < 8.4

class PhpVersion
{
    public function getVersion(): string
    {
        return 'PHP 8.3';
    }
}

var_dump((new PhpVersion())->getVersion());

PHP 8.4

class PhpVersion
{
    public function getVersion(): string
    {
        return 'PHP 8.4';
    }
}

var_dump(new PhpVersion()->getVersion());

Properties and methods of a newly instantiated object can now be accessed without wrapping the new expression in parenthesis.

New Classes, Interfaces, and Functions

New Lazy Objects.
New JIT implementation based on IR Framework.
New request_parse_body() function.
New bcceil(), bcdivmod(), bcfloor(), and bcround() functions.
New RoundingMode enum for round() with 4 new rounding modes TowardsZero, AwayFromZero, NegativeInfinity, and PositiveInfinity.
New DateTime::createFromTimestamp(), DateTime::getMicrosecond(), DateTime::setMicrosecond(), DateTimeImmutable::createFromTimestamp(), DateTimeImmutable::getMicrosecond(), and DateTimeImmutable::setMicrosecond() methods.
New mb_trim(), mb_ltrim(), mb_rtrim(), mb_ucfirst(), and mb_lcfirst() functions.
New pcntl_getcpu(), pcntl_getcpuaffinity(), pcntl_getqos_class(), pcntl_setns(), and pcntl_waitid() functions.
New ReflectionClassConstant::isDeprecated(), ReflectionGenerator::isClosed(), and ReflectionProperty::isDynamic() methods.
New http_get_last_response_headers(), http_clear_last_response_headers(), and fpow() functions.
New XMLReader::fromStream(), XMLReader::fromUri(), XMLReader::fromString(), XMLWriter::toStream(), XMLWriter::toUri(), and XMLWriter::toMemory() methods.
New grapheme_str_split() function.

Deprecations and backward compatibility breaks

The IMAP, OCI8, PDO_OCI, and pspell extensions have been unbundled and moved to PECL.
Implicitly nullable parameter types are now deprecated.
Using _ as a class name is now deprecated.
Raising zero to the power of a negative number is now deprecated.
Passing invalid mode to round() throws ValueError.
Class constants from extensions date, intl, pdo, reflection, spl, sqlite, xmlreader are typed now.
GMP class is now final.
MYSQLI_SET_CHARSET_DIR, MYSQLI_STMT_ATTR_PREFETCH_ROWS, MYSQLI_CURSOR_TYPE_FOR_UPDATE, MYSQLI_CURSOR_TYPE_SCROLLABLE, and MYSQLI_TYPE_INTERVAL constants have been removed.
mysqli_ping(), mysqli_kill(), mysqli_refresh() functions, mysqli::ping(), mysqli::kill(), mysqli::refresh() methods, and MYSQLI_REFRESH_* constants have been deprecated.
stream_bucket_make_writeable() and stream_bucket_new() now return an instance of StreamBucket instead of stdClass.
exit() behavioral change.
E_STRICT constant has been deprecated.

Better performance, better syntax, improved type safety.

Upgrade to PHP 8.4 now!

For source downloads of PHP 8.4 please visit the downloads page. Windows binaries can be found on the PHP for Windows site. The list of changes is recorded in the ChangeLog.

The migration guide is available in the PHP Manual. Please consult it for a detailed list of new features and backward-incompatible changes.

Property hooks RFC Doc

Asymmetric Visibility RFC Doc

#[\Deprecated] Attribute RFC Doc

New ext-dom features and HTML5 support RFC RFC Doc

Object API for BCMath RFC

New array_*() functions RFC

PDO Driver specific SQL parsers RFC

new MyClass()->method() without parentheses RFC Doc

New Classes, Interfaces, and Functions

Deprecations and backward compatibility breaks

Better performance, better syntax, improved type safety.

`#[\Deprecated]` Attribute RFC Doc

New `array_*()` functions RFC

`new MyClass()->method()` without parentheses RFC Doc