Deprecate synchronized classes please!

[IGotD-]

On Tuesday, 6 September 2022 at 10:43:44 UTC, Loara wrote:
>
> You can't send a `synchronized` class to a different thread via 
> `send` \ `receive` unless you make your class `shared`. 
> Phobos's multithreading functions are focusing on `shared` data 
> types at the expense of `synchronized` classes. There isn't any 
> traits that tells you if a class is `synchronized` too.
>

I'm not sure you mean with "send". The point with with 
synchronized classes is that you can use them everywhere, across 
thread boundaries without ownership. If "send" is just a way to 
share the synchronized class upon thread entry as a parameter, 
then I'd say it's a bug and it should be rectified.

> Yes you can still use `synchronized` in you code, but in that 
> case Phobos will go against you when you'll have to share your 
> synchronized classes and force you to cast your classes and 
> make your code less safe.
>

Yes, it's a gap in the inconsistent D design. D shared memory 
model is broken in many ways.

> Also in a `synchronized` class each member becomes `shared`, 
> but this will force you to use atomic operation even if you 
> have exclusive access to data variables. All the stuff around 
> `synchronized` seems poorly designed only as a copy of Java's 
> synchronization and later abandoned.

If all members becomes atomic inside a synchronized class, then 
it's a design error. The whole point of a synchronized class is 
that the members should be normal variables and not atomics.

What is going on here?