Map and Spawn don't mix?

[Andrei Alexandrescu]

On 3/6/11 10:44 AM, Russel Winder wrote:
> If I do:
>
>    auto tasks = new Tid[numberOfTasks] ;
>    foreach ( i ; 0 .. numberOfTasks ) { tasks[i] = spawn (&  partialSum , thisTid , i , sliceSize , delta ) ; }
>
> everything workls as desired, I get parallelism and appropriate scaling.
> However if I try:
>
>    auto tasks = map ! ( ( i ) { return spawn (&  partialSum , thisTid , i , sliceSize , delta ) ; } ) ( iota ( numberOfTasks ) ) ;
>
> the code runs but everything is serialized, no parallelism, no speed up.
>
> I would say this is a bug, but perhaps it is a consequence of the way map works?

I doubt the code ever runs - map is lazy.

Andrei