On 8/15/17 5:27 PM, Arek wrote:
On Tuesday, 15 August 2017 at 10:37:08 UTC, Kagamin wrote:
Well, no wrapper is actually needed here:
class A
{
int method() shared;
}
void consumer()
{
shared a = receiveOnly!(shared A)();
}
void producer()
{
auto cons = spawn(&consumer);
send(cons, new shared A());
}
Yes, but this doesn't compile:
import std.stdio;
import std.concurrency;
struct A
{
int t;
int r;
int method() shared
{
return 0;
}
}
void consumer()
{
shared a = receiveOnly!(shared A)();
}
void main()
{
auto cons = spawn(&consumer);
send(cons, shared A());
}
The issue is that send cannot handle shared value types due to a bug in
the implementation. In essence, there is no reason to send a shared A --
it's an unrelated copy and not actually shared.
You can send a shared reference to an A just fine:
static shared A a;
send(tid, &a); // works
You *should* be able to send a shared(A). There is no reason to disallow
it. But again, it's not super useful.
This very simple code also doesn't compile:
shared struct S
{
int i;
~this()
{
}
}
void main()
{
shared s = shared S();
}
In general, shared structs with postblit and destructor make problems.
postblit should work.
It does look like destructors are a problem. It appears the compiler
attempts to call the destructor while unshared.
-Steve
