PyConf to check if filters are used in the control flow
From https://mattermost.web.cern.ch/lhcb/pl/bghpguya1bbh3dj1np3x3qaaoc
@graven : Note: do we actually check in PyConf that algorithms that are entered in the control flow do return a control flow decision?
@sstahl : I don't think so. If this would be a requirement, one would need to be able to opt out of this as well. (for monitoring, MC checking etc.)
@graven : indeed, you need support for terminal leafs in there... so that check would be too paranoid.
@rmatev : that's an interesting note, we should continue in an issue. Also, how would we check if an algorithm is a filter?
@graven : Could check whether it is the right type of Gaudi::Functional instance -- i.e. one could at compile time when the algorithm is instantiated recognize it, and then a channel is needed to propagate the information into python... (i.e. Gaudi::Functional could be extended to automatically document this)
anyway, that's for an issue, and should be considered as a 'quality of implementation' improvement, which might help people when writing lines to do the 'right' thing more easily... but it is certainly not necessary (and thus not a priority right now)