Tweetable PHP-Non Alpha

I started to try and break the 10 charset limit of PHP non-alpha after @InsertScript showed me that PHP Dev supports [] syntax for arrays. I wondered if it would be possible to break the limit within production PHP. At first I thought you could but then after some testing I found that there was no way to concat without “.” and no way to call a string as a function without $ and =. However since I got into PHP Non-alpha again I thought why not try and improve it and make the code tweetable.
The first hack I found was that underscore is usable in PHP as a string since there is a function called “_”. Therefore we can create 0 by simply doing:
echo +_;
You can also create numbers and arrays using undefined variable references like so:
echo ++$_[];//prints 1

http://www.thespanner.co.uk/2012/12/13/tweetable-php-non-alpha