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In-Reply-To: <AANLkTim9wJSM9XrZu7JHmvX04ZfE+Bikz_-SP+6aJx79@mail.gmail.com>
Date: Thu, 9 Dec 2010 09:09:03 +0100
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To: Nathan Nobbe <quickshiftin@gmail.com>
Subject: Re: [PHP-DEV] Traits expecting interfaces implicitly leads to expensive runtime checks
From: php@stefan-marr.de (Stefan Marr)

Hi Nathan:

On 09 Dec 2010, at 08:44, Nathan Nobbe wrote:

> Hi,
>=20
> I think traits will lend themselves to frequent runtime checking =
against the
> type of class in which they were used.  Consider a trait designed for =
use
> with an Iterator class; the first thing might be to check the type of =
$this.
Why would you need such a check?
You want to ensure that the class that is using your trait obeys a =
certain interface, right?
More specifically, you need it to implement a number of methods of an =
interface, correct?

So, why not asking for it explicitly?


<?php
trait InnerIteratorImpl {
 abstract function next();

 public function apply() {
     do somthing with $this->next() ...
  }
}
?>

Does that what you want it to do?

Best regards
Stefan

--=20
Stefan Marr
Software Languages Lab
Vrije Universiteit Brussel
Pleinlaan 2 / B-1050 Brussels / Belgium
http://soft.vub.ac.be/~smarr
Phone: +32 2 629 2974
Fax:   +32 2 629 3525