[Rivet] [Rivet-svn] r2876 - in trunk: . bin include/Rivet/Tools src/Analyses src/Core src/Tools

[Andy Buckley]

On 07/02/11 15:08, Frank Siegert wrote:
> Hi Andy,
> 
> sorry for the late reply on this.
> 
> On 31/01/11 16:33, Andy Buckley wrote:
>> On 31/01/11 15:16, David Grellscheid wrote:
>>> Other than Rivet, I can't recall a tool where the env variable
>>> completely overrides the builtin path. The builtin always gets pushed
>>> back in the search queue, but doesn't get removed.
>>
>> That's what we used to do and it always caused problems because of cases
>> where you wanted an analysis with the same name as an existing one, but
>> a different behaviour of some kind.
> 
> Is that really a valid use case? If you want to write your own analysis,
> why should you be able to call it the same as an existing one?
> 
>> We could change the search behaviour
>> (again!) to use that "use first match found" idiom but a) that would
>> require restructuring the analysis loader machinery again, and b) it
>> would make it easily possible to run the wrong version of an analysis
>> just because of search path ordering or similar errors.
> 
> "Wrong version" of the stupidly named analysis from above, or is there a
> more valid use case for where that would happen?

I am probably still living in the past -- we had some previous cases
where this was required because of nasty hacks that needed to be applied
for tuning, but which we couldn't put into the release. It's not a good
argument, and it makes more sense for these weirdo requirements to be
the ones that should be worked around :)

I think there is a consensus that the "use first version found"
behaviour would be a good one, so I withdraw all my flimsy objections. I
think we should assign this as a development task for release 2.0.0 --
some restructuring of the analysis loader system (damn, I thought I
would never have to look at that again) will be needed, and I don't
think we should delay the physics-driven version 1.5.0 to implement this
feature. But if someone else wants to do it now, and quickly, please do so!

See, Rivet design can be a democracy... when it suits me :P

Andy
~BDFL

-- 
Dr Andy Buckley
SUPA Advanced Research Fellow
Particle Physics Experiment Group, University of Edinburgh

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.