On Thursday, 18 October 2018 at 16:24:39 UTC, Manu wrote:
On Thu., 18 Oct. 2018, 5:05 am Patrick Schluter via
Digitalmars-d, < digitalmars-d@puremagic.com> wrote:
On Wednesday, 17 October 2018 at 22:56:26 UTC, H. S. Teoh
wrote:
>> If something might be used by someone else it's better not
>> to touch it, unless one has confirmation it is not used by
>> someone else.
>>
>> This is what shared has to enforce.
>
> Yes. But how can the compiler statically verify this?
> Because if it cannot be statically verified, then somewhere
> along the line we have to trust the programmer. Ergo, it's
> programming by convention, and we all know how effective
> that is.
>
and that is exactly what shared is currently doing. Adding the
rw restriction at least adds a protection for inadvertantly
changing a shared object, a thing that doesn't exist now.
What cracks me up with Manu's proposal is that it is its
simplicity and lack of ambition that is criticized the most.
shared is a clusterfuck, according to what I gathered from the
forum, I never had yet to use it in my code. Manu's idea makes
it a little less of a clusterfuck, and people attack the idea
because it doesn't solve all and everything that's wrong with
shared. Funny.
Elaborate on this... It's clearly over-ambitious if anything.
What issues am I failing to address? I'm creating a situation
where using
shared has a meaning, is safe, and doesn't require any unsafe
interactions,
no casts, etc, for users at any level above the bare metal
tooling... How
would you improve on that proposition?
No, your proposition is not the issue here. The problem I see is
the expectation people have with what shared is supposed to do. I
have the impression from reading in this forum about shared that
people expect that just putting a shared in front of a variable
will solve all the concurrency problems in existance.
Your proposition doesn't want to address this utopic goal and
that is a good thing imo. Adding that restriction that you
propose makes explicit what was implied but not clearly stated
until now.
I'm not good enough in D to add more than a meta reflexion on the
subject so I will not follow up on that. I often have the
impression that a lot of things are going slower than necessary
because a mentality where the perfect is in the way of good.
