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Date: Sun, 21 Oct 2012 00:59:01 +0400
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Subject: Generics proposal
From: inefedor@gmail.com (Nikita)

Hello, list. I want to propose generics. For those, who don't know what it i=
s, here's example: say we have a Comment class, that has a method getBody. A=
lso we have Collection class, that implements Traversable. Now, if I want to=
 validate all insertions into collection of comments, I would need to create=
 CommentCollection class, extend it from Collection, and override all the me=
thods that are dealing with adding new elements to collection. Moreover, I c=
an't have any hints from my IDE about type of collection's elements, so if I=
'll have code like this:
foreach ($commentCollection as $comment) {
    $comment->getBody();
}
There will be no way for IDE to know, of what type that object will be.

But there's how I could solve my problem with generics:
class Collection<T> implements Traversable
{
    ...
    public function add(T $element){}
}
$collection =3D new Collection<Comment>();

$collection->add(new Comment());

$collection->add("that will be error");

Actually, that's, again, all about type hinting. If we went so far with scal=
ar type hinting, then generics would also be a good addition.

So, what you think?=