RFC Proposal : Allows calling non-static public methods through the __callStatic magic method instead of throwing an error.

Le 17 févr. 2024 à 16:51, Larry Garfield larry@garfieldtech.com a écrit :

Hi.
I'd like to propose an RFC, but I don't have the authority.
Below is my suggestion.
If you think this makes sense, please write an RFC for me.
Sincerely.

---

===== Introduction =====
Allows calling non-static public methods through the __callStatic magic
method instead of throwing an error.

===== Proposal =====

From a conceptual perspective:
It goes without saying that calling a non-static method statically will
result in an error.
However, a confusing situation occurred when the __callStatic magic
method exists.
Non-public methods can be called, but public methods cannot.
This is the opposite of the method visibility policy.

From a practical point of view:
If you can call Non-static public methods through the __callStatic
magic method, you can write code like Laravel ORM more simply and tidy.

<code> User::foo()->bar(); </code>

==== Before ====

<code> class Foo { protected static ?Foo $instance = null;

public static function __callStatic($method, $args)
{
$instance = self::$instance ?? self::$instance = new static();
return $instance->__call($method, $args);
}

public function __call($method, $args)
{
if (method_exists($this, $method)) {
return $instance->$method(...$args);
}

   return $this;

}

protected function bar()
{
echo METHOD . '<br />';

   return $this;

}

protected function baz()
{
echo METHOD . '<br />';

   return $this;

}
}

Foo::bar()->baz();
(new Foo())->bar()->baz();
</code>

There is no error, but the concept of method visibility is broken.
All Non-public methods can be called at instance scope.

==== After ====

<code> class Foo { protected static ?Foo $instance = null;

public static function __callStatic($method, $args)
{
$instance = self::$instance ?? self::$instance = new static();

   if (method_exists($instance, $method)) {
       return $instance->$method(...$args);
   }

   return $instance;

}

public function bar()
{
echo METHOD . '<br />';

   return $this;

}

public function baz()
{
echo METHOD . '<br />';

   return $this;

}
}

Foo::bar()->baz();
(new Foo())->bar()->baz();
</code>

This is more tidy.
Only public methods are callable at instance scope.

That calling bar() works at all in this example is rather accidental. The whole point of a non-static method is that it has an implicit required $this argument to it. Without a required argument, a method cannot be called, because it is supposed to fail.

In fact, even your "before" example fails: https://3v4l.org/moH0s

It does work after having corrected the obvious bug in the bar() method.

I don't think what you describe is even possible, nor would it be a good idea.

Why wouldn’t it possible? Couldn’t the engine invoke __callStatic() instead of complaining that the targeted method is not static? (I don’t have opinion on whether it is a good idea, though)

—Claude