Properties (hooks) and inheritance
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@iluuu1994 is already working on this.
Since Aug 15, 2024.
Category: Engine
Feature
Status: Verified
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Description
Description
Referenced RFC https://github.com/php/php-src/pull/13455
The following code:
<?php
interface ExampleInterface {} // parent
interface MutableExampleInterface extends ExampleInterface {} // child
final class Example implements MutableExampleInterface {} // impl
// parent provider
interface ExampleProviderInterface
{
// Any type that implements ExampleInterface can be read
public ExampleInterface $property { get; }
}
// child provider that "overrides" parent definition
interface MutableExampleProviderInterface extends ExampleProviderInterface
{
// Any type that implements (MutableExampleInterface & ExampleInterface) can be read + write
// We supplement the object with the set method
public MutableExampleInterface $property { get; set; }
}
// An implementation that uses implementation
final class ExampleProvider implements MutableExampleProviderInterface
{
public Example $property { // << implementation
// We can return the implementation, because it implements (MutableExampleInterface & ExampleInterface)
get => $this->property;
// Any instance of ExampleInterface is allowed for set, since it satisfies the covariance condition
set (ExampleInterface $v) => $this->property = new Example($v);
}
}
Resulted in this output:
Fatal error: Type of ExampleProvider::$property must be MutableExampleInterface (as in class MutableExampleProviderInterface)
But I expected this output instead:
*nothing*
Same code (logic) using getters and setters instead of properties: https://onlinephp.io/c/4e180
interface ExampleInterface {}
interface MutableExampleInterface extends ExampleInterface {}
final class Example implements MutableExampleInterface {}
interface ExampleProviderInterface
{
public function getProperty(): ExampleInterface;
}
interface MutableExampleProviderInterface extends ExampleProviderInterface
{
public function getProperty(): MutableExampleInterface;
public function setProperty(MutableExampleInterface $value): void;
}
final class ExampleProvider implements MutableExampleProviderInterface
{
public function getProperty(): Example {}
public function setProperty(ExampleInterface $value): void {}
}
Ping @iluuu1994 (again) ^_^
PHP Version
PHP 8.4-beta1
Operating System
No response
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