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Date: Mon, 11 Jun 2012 22:01:25 +0100
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Subject: Re: [PHP-DEV] Support negative indexes for arrays and strings
From: marc@easen.co.uk (Marc Easen)

On 11/06/12 20:13, Stas Malyshev wrote:
> Hi!
>
>>> Can be:
>>> $var = 'abc';
>>> echo $var[-1];
>> This seems simple enough for a hard-coded -1, but...
>>
>> Would $var[-2] be strlen($var) - 2 and so on?
> The main question is what happens with "foo"[-4] or ['x'][-2].
>
>> And then one would expect some rather complex logic to compute -N for
>> $var[-N]
> I don't see much of complex logic here, but $a[2] = 'a' would create a
> new array element if it does not exist, while $a[-2] can't. Not a big
> issue, but somewhat inconsistent I guess.
>

Please note I'm not referring the negative indexes in arrays, just 
strings. As I see strings as being simpler to implement and produce a 
greater benefit compared to supporting negative indexes for arrays. As 
arrays are more complex structures and adding this behaviour would 
complicate things somewhat.