(j3.2006) (SC22WG5.5029) WG5 vote on draft TS on further coarray features
Van Snyder
van.snyder
Sun Jul 21 18:33:11 EDT 2013
An alternative to a new this_team() intrinsic, or executing a FORM
SUBTEAM statement, is a team variable in ISO_Fortran_env, whose value is
the initial team.
I still think the idea of putting "team_variable ::" ahead of
cosubscripts is a bad idea. I would rather see a syntax for
coassociation, along the lines of the ASSOCIATE statement, in the CHANGE
TEAM statement.
This discussion worries me. Like King Ronald, we've mounted our horse
and are thundering down the road in every direction, designing stuff
that nobody understands yet. It looks like much of this stuff has had
only a few moments' reflection before being proposed to be cast in
concrete. Sure, Cray might have done some of it already, and their
customers might use it successfully, but that doesn't mean it's the best
solution, or even a good one.
I'd rather see more discussion, introspection, consensus, and
experience, and less controversy, before we rush to publish a
definitive solution as a Technical Specification that is almost promised
to end up as part of the standard.
Tobias Burnus wrote:
> Bill Long wrote:
>
>> If the application needs a name for the initial team, you can form a
>> team in the main program with every image specifying the same team (1).
>> For the purposes of cosubscripts, this team is the same as the
>> initial team.
>>
>
> I somehow thought that one additionally needs a "change team", but I now
> think that a "form subteam" should be sufficient - which makes the code
> cleaner than I initially feared.
>
> Thus, the advantage of the proposed new intrinsic (e.g. "this_team()")
> is smaller.
>
> PRO new intrinsic: The code is clearer than "form subteam(1, var)". And
> it avoids a synchronization (which is relatively slow)
> CON new intrinsic: It pollutes the namespace without providing a
> substantial new features.
>
> Tobias
> _______________________________________________
> J3 mailing list
> J3 at mailman.j3-fortran.org
> http://mailman.j3-fortran.org/mailman/listinfo/j3
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.j3-fortran.org/pipermail/j3/attachments/20130721/94ffd06c/attachment.html
More information about the J3
mailing list