What is static return type in PHP 8?

The static return type in PHP 8 means the method is expected to return an instance of the class it's called on, including any child class. 1. It enables late static binding, ensuring the returned value matches the calling class's type. 2. Compared to self, which always refers to the defining class, and \\ClassName, which forces a specific class, static adapts to inheritance. 3. It is ideal for factory methods, fluent interfaces, and singletons where subclasses need to return their own type. 4. This improves code design by reducing boilerplate, enabling accurate type hints, and supporting cleaner inheritance chains. 5. Practical examples include Laravel model factories and logger implementations that respect subclass types automatically.

When you see a static return type in PHP 8, it means the method is expected to return an instance of the class it's called on — not just the class it was defined in, but potentially a child class if it's inherited. This behavior makes static different from self, which always refers to the class where the method was originally defined.

What does static mean as a return type?

In PHP, static as a return type was introduced to support late static binding. It tells PHP that the returned value should be of the same type as the class that was used to call the method — even if it's a child class.

For example:

class ParentClass {
    public static function create(): static {
        return new static();
    }
}

class ChildClass extends ParentClass {}

$obj = ChildClass::create(); // Returns an instance of ChildClass

This helps when you're building classes meant to be extended, because using static ensures that methods return instances of the correct subclass automatically.

When should you use static instead of self or the class name?

Use static when you want inheritance to affect the return type. Here’s how it compares:

• self: Always returns the type of the class where the method is defined.
• static: Returns the type of the class that was called (could be a subclass).
• \ClassName: Forces the exact class type, regardless of context.

So if you're writing a factory method or any kind of method that subclasses might override and return their own type, static is your friend.

A common place this shows up is in Laravel or other frameworks, especially with model factories and query builders.

How does this improve code design?

Using static return types gives developers more flexibility when designing object hierarchies. It reduces the need for overriding methods just to change the return type in subclasses.

Here are a few benefits:

• Cleaner inheritance chains.
• More accurate type hints without duplication.
• Less boilerplate code in subclasses.

Without static, every time you extend a class that returns self, you’d have to override that method just to return the right type. With static, that step becomes unnecessary.

Also, IDEs and static analyzers can better understand what type to expect, which improves auto-completion and error checking.

Practical use cases

Here are a few places where static really shines:

• Factory methods – Like the example above, creating objects that respect the caller's class.
• Fluent interfaces – If you're chaining method calls and returning $this, using static ensures correct type inference.
• Singleton patterns – Especially when extending base classes that implement singleton logic.

Example:

class BaseLogger {
    protected static $instance;

    public static function getInstance(): static {
        if (!static::$instance) {
            static::$instance = new static();
        }
        return static::$instance;
    }
}

class CustomLogger extends BaseLogger {}

$logger = CustomLogger::getInstance(); // Returns CustomLogger instance

That’s basically it. The static return type isn’t complicated, but it fills a useful gap when working with inheritance in PHP 8.

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