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Date: Thu, 12 Dec 2013 20:02:17 +0000
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Subject: [PROPOSAL] Alphanumeric decrement
From: ajf@ajf.me (Andrea Faulds)

Good evening,

At present, it's possible to increment (++) an alphanumeric string, such 
that "a" when incremented becomes "b", "z" becomes "aa", and so on.

However, it's irritated me that the same is not true for the decrement 
(--) operator. At present, "aa" when decremented stays as "aa", and "b" 
when decremented stays as "b". This lack of symettry is counterintuitive 
to me. I don't think it's what you would expect here.

So I've written a patch which would change this. "aa" when decremented 
would be "z", and "b" when decremented would be "a". It also handles 
decrementing "a", which becomes "0". This creates an interesting new 
asymettry: {$a = "a"; $a--; $a++;} will result in $a being integer 1. I 
think it's better than the previous behaviour, though, which resulted in 
"b".

The diff is here: 
https://github.com/TazeTSchnitzel/php-src/compare/php:PHP-5.6...AlphanumericDecrement

My aim is to try and get this into PHP 5.6, if people are interested. 
Thoughts?

-- 
Andrea Faulds
http://ajf.me/