The disadvantage of purity

[Dominikus Dittes Scherkl]

On Sunday, 29 December 2019 at 10:40:23 UTC, sarn wrote:
> On Sunday, 29 December 2019 at 10:02:48 UTC, berni44 wrote:
>> I have not yet a deep understanding of purity, so maybe there 
>> is a way arround this problem I cannot see due to my limited 
>> knowledge. Any ideas?
>
> Here's a generic pattern you could use:
>
> T foo(Value x) pure
> {
>   static T impl(Value x, ref State s) pure
>   {
>     // ...code recursively calling impl and tracking state with 
> mutable s
>   }
>   State s;
>   return impl(x, s);
> }

Yes, exactly this.