std.concurrent Tid vector initialization problem

[Charles Hixson via Digitalmars-d-learn]

On Sunday, 28 June 2015 at 09:59:29 UTC, Marc Schütz wrote:
> On Sunday, 28 June 2015 at 01:02:02 UTC, Charles Hixson wrote:
>> I'm planning an application where a series of threads each 
>> ...gn.  Does anyone have a better idea?
>>
>> (The rough estimate of the number of Tids is six, but that's 
>> likely to change from run to run.)
>
> The most elegant solution I can think of is this:
>
> struct Go { }
>
> __gshared const Tid[] allTids;
>
> void myfunc(...) {
>     receiveOnly!Go();
>     // do the work
> }
>
> shared static this() {
>     Tid[] tids;
>     foreach(thread; threads)
>         tids ~= spawn(&myfunc, ...);
>     *cast(const(int)[]*) &allTids = tids;
>     foreach(tid; allTids)
>         tid.send(Go());
> }
>
> I believe the cast is not even undefined behaviour, because 
> it's not immutable, but I'm not sure. But the const-ness guards 
> against accidental modification of `allTids` by a thread.
>
> Alternatively, you could make `allTids` private, provide a 
> public getter, and implement the threads in another module.
>
> Or you could simply leave the global array mutable and be 
> careful not to modify it.

Thanks.  That sounds similar to the approach that I had though 
of, except that you're doing it in a static this().

(I'd have answered sooner, but my D email seems to have died.  
Only the D groups are currently dead now, though my entire 
account was dead for a couple of weeks.  [AT&T])