Hi Doug:

>From dougo@ccs.neu.edu Sun Nov 15 16:05:07 1998
>To: Karl Lieberherr <lieber@ccs.neu.edu>
>Cc: generic@ccs.neu.edu
>Subject: Re: API for AP library
>
>Karl Lieberherr writes:
> > The API below looks good to me. Regarding the returned information,
> > we would like to get back whether the class graph and strategy graph 
> > are compatible. You probably know this from the forward sweep?
>
>Currently in demjava I only check for the existence of some path, by
>checking !tg.vertices().isEmpty().  Probably a better way would be to
>check that all vertices in the strategy graph also exist in the
>computed traversal graph.

Let's keep your current check but add a second. 
There are different predicates one
would like to check on a traversal graph:
1. the one you have: at least some path from some source to some target.
2. the current "official" definition of compatability: each edge in the
   strategy graph must have a corresponding path in the class graph.
   This implies: that all vertices in the strategy graph also exist in the
   computed traversal graph.

>
>Also, one major thing that is missing in the interface is a way to get
>information about which copies of the nodes and edges are in the
>traversal graph; currently you can only get the CG subgraph, not the
>actual path set.  (Actually, you can-- the generate module needs it--
>but it's not documented.)  I'm still thinking about what the best API
>for this is; will this be needed for the bean projects?

The bean project can make a lot of progress by just working
with the CG subgraph, also called  propagation graph.

>
>--Doug
>
-- Karl