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Subject: Re: [PHP-DEV] Object Type Casting Reloaded
From: sebastian@php.net (Sebastian Bergmann)

Am 22.04.2019 um 23:47 schrieb Benjamin Morel:
> These combine into a third advantage: readability. Today's equivalent of
> the above one-liner could be:
> 
>      /** @var EmailService $service */
>      $service = $diContainer->get('email.service');
>      if (! $service instanceof EmailService) {
>          throw new TypeError('Expected instance of EmailService, ...');
>      }

Today's equivalent is, at least for me, is this one-liner:

     assert($service instanceof EmailService);

This way the IDE knows what type $service is supposed to be and there will 
be an exception at runtime (given the appropriate configuration) when this 
is not the case.

Personally, I prefer hand-written factories that have an explicit 
createEmailService() method with a :EmailService return type declaration, 
for example, over the implicitness of a dependency injection container as 
the latter disguises and obscures dependencies.