DIP 1014

[Shachar Shemesh]

On 03/10/18 17:29, Stanislav Blinov wrote:
>> OMG, that's so simple!!! Why didn't I think of it?
>>
>> Oh wait, I did.
> 
> Now I see why sometimes your posts are greeted with hostility.

Yes. I am actually sorry about that. I was responding to your assumption 
that I'm wrong. Had your post been phrased as "why didn't you", instead 
of "you're wrong wrong wrong" I wouldn't have responded that way.

Like I said, I am sorry.


 > Allow me to further illustrate with something that can be written in 
D > today:

I am not sure what you were trying to demonstrate, so instead I wanted 
to see if you succeeded. I added the following to your Tracker struct:

      ~this() {
         writefln("%s destructed", &this);
         assert(counter is null || counter is &localCounter);
     }

I.e. - I am asserting if a move was not caught. The program fails to run 
on either ldc or dmd. To me, this makes perfect sense as for the way D 
is built. In essence, opAssign isn't guaranteed to run. Feel free to 
build a struct where that assert passes to convince me.

Here is the flaw in your logic:

     void opAssign(Tracker rhs)

rhs is passed by value. This means that already at the point opAssign is 
called, rhs *already* has a different address than the one it was passed 
in with. I did not follow your logic on why this isn't so, but I don't 
see how you can make it not so without changing the ABI quite drastically.

Shachar