shared - i need it to be useful

[Erik van Velzen]

On Thursday, 18 October 2018 at 19:26:39 UTC, Stanislav Blinov 
wrote:
> On Thursday, 18 October 2018 at 19:04:58 UTC, Erik van Velzen 
> wrote:
>> On Thursday, 18 October 2018 at 17:47:29 UTC, Stanislav Blinov 
>> wrote:
>>>
>>> Doesn't work. No matter what you show Manu or Simen here they 
>>> think it's just a bad contrived example. You can't sway them 
>>> by the fact that the compiler currently *prevents* this from 
>>> happening.
>>
>> Manu said clearly that the receiving thread won't be able to 
>> read or write the pointer.
>
> Yes it will, by casting `shared` away. *Just like* his proposed 
> "wrap everything into" struct will. There's exactly no 
> difference.
>

Casting is inherently unsafe. Or at least, there's no threadsafe 
guarantee.

>> Because int or int* does not have threadsafe member functions.
>
> int doesn't have any member functions. Or it can have as many 
> as you like per UFCS. Same goes for structs. Because "methods" 
> are just free functions in disguise, so that whole distinction 
> in Manu's proposal is a weaksauce convention at best.
>
>> You can still disagree on the merits, but so far it has been 
>> demonstrated as a sound idea.
>
> No, it hasn't been.

I think you are missing the wider point. I can write 
thread-unsafe code *right now*, no casts required. Just put 
shared at the declaration. The proposal would actually give some 
guarantees.