Optimisation possibilities: current, future and enhancements

[ag0aep6g via Digitalmars-d]

On 08/26/2016 10:09 PM, Patrick Schluter wrote:
> Yes. The optimisation of removing the second call is only possible if
> there is no access using the this pointer. The call to setN() (or any
> member function using the mutable this pointer), will mandate the
> compiler to call getN() again.

If setN is called or not does not affect getN's purity, though. You 
wrote that (the method) getN is not pure and should be rejected by the 
compiler, but both variants (method and function) are equally pure or 
impure.