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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 20:28, Richard Lynch wrote:
> On Mon, June 11, 2012 2:13 pm, Stas Malyshev wrote:
>>> 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.
> $n = some_incredibly_long_and_complex_computation();
> //and, for real fun, sometimes it returns positive, and sometimes
> negative.
>
> $s = $var[$n];
If $n is a negative value, an E_NOTICE will be triggered. To not do
> if ($n<  0){
> //whatever
> }
> else{
> //something entirely different
> }
Prior to your string offset can be looked at being bad practice.