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Date: Fri, 17 Mar 2017 20:57:58 -0500
Message-ID: <CAESVnVr=BBpYJT2eQkaC8ZOcTrHPybzDwmb1s1LFDbCnRpepkQ@mail.gmail.com>
To: David Rodrigues <david.proweb@gmail.com>
Cc: Niklas Keller <me@kelunik.com>, PHP Internals <internals@lists.php.net>
Content-Type: text/plain; charset=UTF-8
Subject: Re: [PHP-DEV] Let range() return a generator?
From: pollita@php.net (Sara Golemon)

On Fri, Mar 17, 2017 at 8:40 PM, David Rodrigues <david.proweb@gmail.com> wrote:
> There are some way to PHP be flagged before run some function, and
> understand that you wants to return a Generator instead of array?
> For instance: new Generator(range(1, 1000)) makes range() work like a
> generator instead of return an array - it's an alternative to avoid new
> keywords.
> Or, maybe, some side implementation like Generator::range(1, 1000),
> Generator::array_values($array), etc. (Currently, for instance, we can
> simulate the range() Generator, but not array_values())
>
Why would array_values() as a generator be difficult?

function generate_values(Traversable $in) {
  foreach ($in as $k => $v) {
    yield $k => $v;
  }
}

In general, your `new Generator($arr)` concept misses most of the
usefulness of using a generator since arrays are already traversable,
and you've already allocated all the space of a full container.
Where's the benefit from making it a generator?

-Sara