const(X) member of Y

[Dan]

On Wednesday, 6 February 2013 at 22:29:49 UTC, Maxim Fomin wrote:
> Yes, because this(const this) is not a copy constructor or a 
> postblit, it is a simple constructor. X(x) will print "Hi". 
> This is unintuitive, but parameter names can be omitted and 
> this leads to confusion between struct postblit and struct 
> constructor which has first argument of its own type.

Thanks, I did not know that. I think I see it, now:
   auto x3 = X(x);
   auto x4 = x;

The first prints "Hi", the second not. So it is not a "copy 
constructor", but rather a "simple constructor" that would allow 
for performing a copy. I assume the syntax "auto x3 = X(x)" is 
the only way this would be called, and by-value parameter passing 
would never invoke 'this(const this)'.

This begs the question:

Which of these do you choose and for what reasons:
- this(this){}
- this(this)const{}
- this(const this){}

Also, has any of this detailed information made it into the 
language spec?

Thanks
Dan