PHP 8.4 is now available on servers managed by ServerPilot. There are many improvements, changes, new features, and deprecations in PHP 8.4.

Here we'll provide a summary of the most important changes in PHP 8.4. For the full list of changes, see PHP's official documentation on migrating code from PHP 8.3 to 8.4.

Changes in PHP 8.4

New Features in PHP 8.4

Property Hooks

Object properties may now have additional logic associated with their get and set operations. Learn more.

Asymmetric Property Visibility

Object properties may now have their set visibility controlled separately from the get visibility. Learn more.

Lazy Objects

It is now possible to create objects whose initialization is deferred until they are accessed. Learn more.

#[\Deprecated] attribute

The new Deprecated attribute can be used to mark functions, methods, and class constants as deprecated. Learn more.

Chaining new expressions without parentheses

new expressions with constructor arguments now allow chaining method calls, property accesses, etc. without enclosing the expression in parentheses. Learn more.

Improved Debugging Info for WeakReference

Getting the debug info for WeakReference will now also output the object it references, or null if the reference is no longer valid. Learn more.

Improved Debugging Info for Closure

The output of Closure::__debugInfo() now includes the name, file, and line of the Closure. Learn more.

Defining Identical Symbols in Different Namespace Blocks

Exiting a namespace now clears seen symbols. This allows using a symbol in a namespace block, even if a previous namespace block declared a symbol with the same name. Learn more.

New PCRE (regular expressions) features

Spaces are now allowed between braces in Perl-compatible items. Variable-length lookbehind assertions are now supported. Learn more.

New cURL features

New cURL options accept callables to be called either after the connection is made or throughout the request lifetime. Also, the curl_getinfo() now returns a posttransfer_time_us key with the total request time. Learn more.

New Function request_parse_body() in PHP 8.4

The new request_parse_body() function in PHP 8.4 allows parsing RFC1867 (multipart) requests in non-POST HTTP requests. The addition of this function fixes a popular PHP bug from 2011.

// Parsing a PUT request
[$_POST, $_FILES] = request_parse_body();

var_dump($_POST);  // [...]
var_dump($_FILES); // [...]

Learn more.

Backward-Incompatible Changes in PHP 8.4

Changes in PHP 8.4 that are not backward-compatible will prevent code written for earlier PHP versions from working in PHP 8.4

Removal of E_STRICT error level

The E_STRICT error level has been removed, as it was no longer in use within the PHP engine. The E_STRICT constant has also been deprecated. Learn more.

exit() and die() behavior changes

The exit() and die() language constructs now behave more like functions. This means they can now be passed like callables. Learn more.

Deprecations in PHP 8.4

• Calling trigger_error() with error_level being equal to E_USER_ERROR is now deprecated. Such usages should be replaced by either throwing an exception or calling exit().
• Because the E_STRICT error level was removed, this constant is now deprecated.

Extensions moved to PECL in PHP 8.4

IMAP

Starting with PHP 8.4, the IMAP extension is no longer part of PHP core. Instead, the IMAP extension can be installed through PECL.

Pspell

Starting with PHP 8.4, the Pspell extension is no longer part of PHP core. Instead, the Pspell extension can be installed through PECL.

How to Switch to PHP 8.4

You can change an app to use PHP 8.4 through your app's Settings in ServerPilot. If your app does not work with PHP 8.4, you can easily change back to the PHP version you were using before.

As always, please contact us if you have any questions.