Graph-friendly instance navigation/query

[GoogleCodeExporter]

It is very difficult to navigate / query the A4 instance graph with the gui.
The A4 VizGUI has a very fast system for highlighting edges in the graph;
however, it is very difficult to see the different paths between a pair of
vertices.

Suggestion: add context menus to make multiple edge/vertex selections and
to perform a user-defined operation on the selected elements.
How should we specify the user-defined operation?

How about letting the user write an expression in a specially-configured A4
evaluator to edit/debug the operation and display back the results
as either a new view or as a highlighting on top of the current visualisation.

Original issue reported on code.google.com by daniel.l...@gmail.com on 26 Mar 2008 at 12:41

[GoogleCodeExporter]

This issue looks more related to A4 than A4E, but I let it here since A4 does 
not
have for the moment a public issue tracking system.

Felix, you are free to comment here the issue regarding A4.

Original comment by daniel.l...@gmail.com on 26 Mar 2008 at 12:43

[GoogleCodeExporter]

A4E provides A4 with a well-known plugin architecture we can use to extend A4 
for
various domain/application-specific needs including custom rules for navigating
instance graphs. From this perspective, A4 simply needs to provide access to the
necessary information to A4E which in turn makes it available to other Eclipse
plugins where custom instance navigation & user interaction rules can be 
defined.

Original comment by nicolas....@gmail.com on 26 Mar 2008 at 3:41