Re: [pooma-dev] template idiom in the Blitz stencils; TList as a Domain simplification

[Scott Haney]

On Thursday, June 7, 2001, at 07:31 AM, Allan Stokes wrote:

> There might be a case for adopting a TList mechanism to handle vararg
> constructs in Pooma.  The TList itself contains all the nasty code
> replication.  There would no longer be a need for Pooma components to
> replicate member functions on rank.
>
> I don't know to what extend vararg constructs are currently exposed in 
> user
> level contexts, or how much of an imposition it would be to require 
> users to
> package their varargs.
>
> A possible compromise would be to retain the functions for 1 to 3
> dimensions, and only require packaging for extended ranks.  Is having 
> three
> versions any better than having seven?
>
> I'm tossing this construct out first, because it's the least "C++ 
> compliant"
> of all the conveniences which Domain presently offers.  Allowing 
> integers to
> act as a domain type is also a hassle, but at least it's a hassle the
> language endorses.


Hi Allan,

Having one function would be wonderful from an implementation 
perspective; however, I believe that asking the users to package their 
domains would be viewed as ugly and onerous. Providing 7 versions of 
some functions really isn't all that big of a deal, certainly not 
significantly harder than providing 3.

I thought that our approach was C++-compliant. Could you explain where 
it falls short here?

As for integers appearing in a mix of domains, one could legitimately 
argue that this adds a lot of complexity that might better be handled in 
other ways: for example, having  slices require a specific syntax and 
doing indexing with a separate set of member functions.

I do like Todd's approach of defining the stencils. It probably wouldn't 
be horribly hard to try a similar thing with POOMA . Are you interested 
in pursuing a prototype of, say, a cell->cell divergence for comparison 
purposes?

Scott