PHP 8.4 Released with Property Hooks, Simplified Class Instantiation, and More Enhancements

"PHP 8.4 Released with New Array Find Functions, Property Hooks, Simplified Class Instantiation, and More" 

# New Array Find Functions in PHP 8.4

 PHP 8.4 introduces new array find functions, including: - `array_find()` - `array_find_key()` - `array_any()` - `array_all()`

PHP Property Hooks

Property hooks in PHP are inspired by languages like Kotlin, C#, and Swift. The syntax includes two variants, resembling short and multi-line closures.

class User implements Named
{
    private bool $isModified = false;
 
    public function __construct(
        private string $first,
        private string $last
    ) {}
 
    public string $fullName {
        // Override the "read" action with arbitrary logic.
        get => $this->first . " " . $this->last;
 
        // Override the "write" action with arbitrary logic.
        set {
            [$this->first, $this->last] = explode(' ', $value, 2);
            $this->isModified = true;
        }
    }
}

Property hooks will help remove boilerplate of property getters and setters, allowing a property to define access and updates using hooks.

New MyClass()->method() Syntax Without Parentheses

Previously, when using member access during instantiation, it was required to wrap the new MyClass() call in parentheses, or a parse error would occur. The proposed new syntax allows you to access constants, properties, and methods without the need for extra parentheses:

// Wrapping parentheses are required to access class members
$request = (new Request())->withMethod('GET')->withUri('/hello-world');
 
// PHP Parse error (<= PHP 8.3): syntax error, unexpected token "->"

This update addresses a minor issue, making class member access simpler by eliminating the need for surrounding parentheses or a static constructor method. The syntax change also brings PHP closer in line with other C-based languages like Java, C#, and TypeScript, which don't require parentheses around member access.

Create a DateTime from a Unix Timestamp

In PHP 8.4, creating a DateTime from a Unix timestamp becomes more convenient with the new createFromTimestamp() method. This method supports both standard Unix timestamps and timestamps with microseconds.

$dt = DateTimeImmutable::createFromTimestamp(1718337072);
$dt->format('Y-m-d'); // 2024-06-14
 
$dt = DateTimeImmutable::createFromTimestamp(1718337072.432);
$dt->format('Y-m-d h:i:s.u'); // 2024-06-14 03:51:12.432000

In earlier versions of PHP, there are a few ways to create a DateTime instance from a timestamp, such as the createFromFormat() method:

$dt = DateTimeImmutable::createFromFormat('U', (string) 1718337072);
// DateTimeImmutable @1718337072 {#7948
//   date: 2024-06-14 03:51:12.0 +00:00,
// }
 
$dt = DateTimeImmutable::createFromFormat('U.u', (string) 1718337072.432);
// DateTimeImmutable @1718337072 {#7950

//   date: 2024-06-14 03:51:12.432 +00:00,
// }

New mb_ Functions in PHP 8.4

PHP 8.4 introduces multi-byte string support for common functions like trim, ltrim, rtrim, ucfirst, and lcfirst with the new mb_ variants:

• mb_trim()
• mb_ltrim()
• mb_rtrim()
• mb_ucfirst()
• mb_lcfirst()

#Asymmetric Property Visibility

Starting in PHP 8.4, properties may also have their visibility set asymmetrically with a different scope for reading and writing

class Book
{
    public function __construct(
        public private(set) string $title,
        public protected(set) string $author,
        protected private(set) int $pubYear,
    ) {}
}
 
class SpecialBook extends Book
{
    public function update(string $author, int $year): void
    {
        $this->author = $author; // OK
        $this->pubYear = $year; // Fatal Error
    }
}
 
$b = new Book('How to PHP', 'Peter H. Peterson', 2024);
 
echo $b->title; // How to PHP
echo $b->author; // Peter H. Peterson
echo $b->pubYear; // Fatal Error