Look and think good things about D

[qznc]

On Friday, 15 November 2013 at 01:09:53 UTC, bearophile wrote:
> I have created two interesting D entries for this Rosettacode 
> Task, is someone willing to create a Reddit entry for this? 
> They show very different kinds of code in D.
>
> http://rosettacode.org/wiki/Look-and-say_sequence#D

The fast version is nearly functional, too. Since memory 
management is not considered a side effect there is only the 
printfs. If the printfs are wrapped into "debug", the function is 
pure.