Re: [Condor-devel] RFC: an implementation of classads enhanced with macro evaluation

[Alan De Smet <adesmet@xxxxxxxxxxx>]

Erik Erlandson <eje@xxxxxxxxxx> wrote:
> An interesting use case for this extension is that it would allow a
> system to be configured using classads.  For example, in theory condor
> could be configured using the same classad system that it already uses
> for all its other data.

I like the idea of ClassAds as configuration.  However, there has
been resistance to major changes to the configuration system,
resistance that lead to the most recent overhaul being far scaled
down from the original design.  A complete replacement with a
ClassAd based system would be an even bigger step.  I'm skeptical
that such a change is politically feasible.  Without a strong use
case like configuration, the functionality seems like unnecessary
complexity.

> (If you happen to notice that this implementation is in Prolog,
> do not be alarmed -- everything about this implementation and
> its interface could be ported to something like ANTLR and give
> it internal representations for C++, python, ruby, etc).

I think you're proposing rewriting the ClassAd library from
scratch and adding a new dependency (ANTLR).  Is there a reason
it's not possible or appropriate to add this functionality to the
existing, well tested library?  Or did I misunderstand?

-- 
Alan De Smet                 Center for High Throughput Computing
adesmet@xxxxxxxxxxx                       http://chtc.cs.wisc.edu