inout and opApply

[Shachar Shemesh via Digitalmars-d]

On 24/06/16 01:22, Steven Schveighoffer wrote:

> Considering the possible use cases for something like this, I think we
> are better off having this limitation than not being able to use opApply
> with inout.
>
> -Steve

I am not sure I followed the discussion correctly. If I did, however, it 
seems to me the following would also become impossible:

size_t numElements(T)(const ref T val) {
   size_t num;

   foreach(i; val) {
     num++;
   }

   return num;
}

If "val" being const means that the delegate passed to opApply must also 
be const, the meaning is that that delegate may not change "num", which 
seems, to me, unworkable.

All assuming I correctly understood your suggestion.

Shachar