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Date: Mon, 23 Jul 2012 00:49:00 -0700
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To: Alex Aulbach <alex.aulbach@gmail.com>
Cc: Nikita Popov <nikita.ppv@gmail.com>, Nikita Popov <nikita.ppv@googlemail.com>, 
	PHP internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary=14dae93404f19f2d3804c57a7ad2
Subject: Re: [PHP-DEV] Re: Generators in PHP
From: pollita@php.net (Sara Golemon)

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>
>
> My first thought was how could someone reading the code see, that it
> is a generator?
>

Somewhat snarky answer: By documenting the code in the first place.

Yeah, I know, we all inherit other people's code and the other person never
writes comments.

I don't think this is as big of a problem in practice, however.  If you're
looking at the function to understand what it does, you're certainly
looking at statements like "return $foo;" already, right?  Why would "yield
$foo;" be any more stealthy?

You posit that future engineer will have to spend hours understanding what
generatorX does because it's 50+ lines long and original engineer isn't
around anymore, but if the function is so complex, then future engineer is
going to be spending hours whether or not it's a generator at all.  Code
like that is just bad code.  The fact that it's a generator isn't the
problem, nor is whether it's been explicitly flagged as such.

Hm... not really satisfied with that.  For me this is a little bit
> unlogical, that just a simple function can return an object.
>
> So, how about implementing as a class? I mean: If it is returning a
> class, why not implement it as class?
>
> Because that misses the entire point of generators as simplified
iterators.  What you suggest already exists, it's called: class foo
implements Iterator { /* iterator funcs */ }  Also, it doesn't allow for
generators as class methods:

class foo {
  function bar() {
    yield 1;
  }
}

Since this isn't Java, you can't really do:

class foo {
  class bar implements generator {
    function __generator() {
      yield 2;
    }
  }
}

PS: I would like to see that yield goes hand in hand with the
> iterator-stuff.
>
Curious if you could expand on that.  Generators are iterators, so not sure
what you're asking for.

-Sara

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