Look and think good things about D

[bearophile]

qznc:

>> 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.

In a system that allows you a more fine-graded management of 
effects through an algebra, memory allocation is an effect. It's 
easy to show D functions annotated with "pure" that aren't pure 
at all because of memory allocation.

Bye,
bearophile