"Andreas Hennings" andr...@dqxtech.net – August 17, 2020 7:19 PM

   Interesting stuff!

   https://wiki.php.net/rfc/constructor_promotion
   
<https://cloud.rochette.cc/index.php/apps/mail/redirect?src=https%3A%2F%2Fwiki.php.net%2Frfc%2Fconstructor_promotion>

   I see this for the first time, but I like it :)

   Now to your proposal.

   Just to make sure I understand:
   Would this map the parameters by name or by index?

   -> I assume by index, it makes more sense.

if they are mapped by index it means I can’t benefit from this feature without copying all the optional parameters up to the ones I’m interested in.

Which will probably be even more widespread in the future thx to the Named Paramters RFC: https://wiki.php.net/rfc/named_params#object_initialization

So, I was thinking the opposite, if they are mapped by name it means I can avoid passing some the optional parameters if’m not interested in the first ones

   Does it map to parent constructor parameters, or to parent properties?

   -> I assume to parent constructor parameters, because parent
   properties could be private.

exactly

   Can the 'parent' parameters be intermixed with other parameters?

   -> I assume yes, not allowing it would be an unnecessary limitation.

that was my intent yes

   So if you use the 'parent' syntax, you need exactly as many
   parameters with 'parent' as required by the parent constructor.

   // Parent class

   class B {

      public function __construct($b0, $b1) {

        // The values may or may not be written to properties, it does
   not matter.

      }

   }

   // Child class

   class C extends B {

      public function __construct(parent $x, private $c0, parent $y,
   private $c1) {

        // Implicit: parent::__construct($x, $y);

      }

   }


   On Mon, 17 Aug 2020 at 18:46, Mathieu Rochette <math...@rochette.cc>
   wrote:

       Hi,



       I’m writing a message here to receive feedback on a two ideas
       related to
       class constructors before going more in details with an RFC. I
       hope this is
       appropriate behavior for this list



       With the Constructor Property Promotion accepted in PHP 8,
       there’s a lot
       less of boilerplate when writing class constructors. I’m
       suggesting two
       additional ways of making thing even easier and I hope, readable.



       First: I’d like to be able to automatically transfer a constructor
       property to its parent constructor. I’m thinking of something
       like that:



       ```php

       class MyCommand extends Command

       {

           public function __construct(

               private Connection $connection,

               parent string $name,

           ) {

           }

       }

       ```



       This would be the equivalent of :



       ```php

       class MyCommand extends Command

       {

           public function __construct(

               private Connection $connection,

               string $name,

           ) {

               parent::__construct($name);

           }

       }

       ```



       The second idea is to make the constructor body optional, the
       first example
       would now be:



       ```php

       class MyCommand extends Command

       {

           public function __construct(

               private Connection $connection,

               parent string $name,

           )

       }

       ```



       This would call the parent constructor automatically even if no
       "parent"
       parameter are present. I could even see this enforced by linter
       to avoid
       having logic in the constructors.



       If there is interest I’d like to try writing an rfc and
       implement it. I
       have not much knowledge of the php-src code but I hope this is a
       small
       enough change that I’ll be able to tackle. So, at that time if
       someone is
       interested in mentoring this little project I’d appreciate it :)





       regards,



       Mathieu





--
Mathieu Rochette

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