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To: Niklas Keller <me@kelunik.com>
Cc: Andreas Hennings <andreas@dqxtech.net>, PHP Internals
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Date: Mon, 03 Jul 2017 17:53:39 +0200
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Subject: Re: [PHP-DEV] "Reader" as alternative to Iterator
From: johannes@schlueters.de (Johannes =?ISO-8859-1?Q?Schl=FCter?=)

On Mo, 2017-07-03 at 17:32 +0200, Niklas Keller wrote:

> > That distinction is the reason why next() and valid() are different
> > methods in iterators.
> 
> Not really, Iterator::next() returns void, so could as well return
> bool.

Well, that story is a bit longer and I cut it short. Let's assume we
remove valid and use next's return value. Then we don't know if the
first element exists or not, as next is only called after the first
iteration. An alternative might be using only current() but then we
need a special, magic, return value to mark the end oder references.
Both are bad.

johannes