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Date: Tue, 14 Aug 2012 14:37:48 +0200
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To: Nikita Popov <nikita.ppv@gmail.com>
Cc: Brian Moon <brian@moonspot.net>, PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Generators
From: alex.aulbach@gmail.com (Alex Aulbach)

2012/8/13 Nikita Popov <nikita.ppv@gmail.com>:
>  * After first yield: Recoverable fatal error
>
> So this would allow you to call ->rewind() after creating the
> generator, but will throw an error if you try to do so later.

Hm. I think this looks like a workaround over conceptual problems.
The (in my eyes) "right" behavior would be to call a new instance of
the generator if you rewind and destroy the current (= replace current
generator with a new).

I would prefer to say "this is not an real iterator"; if you want to
make it an real iterator, then implement it yourself.

Otherwise it's like "Ok, we have here a new type of function which
looks enough like a function to be a function, which implements an
iterator which looks enough like an iterator to be an iterator.". :)


I also recommend to say, that generators aren't a good idea if used on
resources, which can't be shared. For example: the file-read-example
doesn't lock. To implement locking new functions or a new class is
needed - hiding complexity.

Generators are (in my opinion) really nice for things which are
already in the memory. Not more or less.

-- 
Alex Aulbach