[erlang-questions] What makes erlang software complex

[Taavi Talvik]

On Nov 7, 2008, at 11:31 PM, Sten Kvamme wrote:

> In imperative programming there is Cyclomatic complexity and N-path
> complexity. What makes an erlang program complex?
>
> Thanks,
> Sten Kvamme


Personally I very much liked Joe Armstrong definition of "clean" and  
"dirty"
in his thesis http://www.erlang.org/download/armstrong_thesis_2003.pdf
section 8.3 page 171-174.

Clean functions are easy - for certain set of input, certain set of  
output
is produced. Probably both cyclomatic and n-path complexity can be  
applied
to them.

Dirty functions either produce side effects or depend on side effects.
And their complexity is unknown, probably somewhere near infinity.

disclaimer - I don't have formal theoretical background to discuss  
this;)

best regards,
taavi