The value of a field of an Event can be a path in a tree-structure. It is possible to use such a path as a key for aggregation. The result is considered as a tree for which the technique of a treemap is available. A Treemap offers a way of walking through a tree that is consistent with mouse and cursor-keys usage in other components of the mainwindow. For a first impression of the intended look and feel of a preliminary version of the mainwindow is given in figure 2.
Indication has no further side-effects.
Only clicking has side-effects. This specification has two parts. The first one is a subclass of MetaRecord in Python, describing all the fields of the new type. With these specifications further conversion is automatic. Because dataformats of events produced by systems or applications tend to be the same for many years, specification of a describing model also has a long life-time.