>From boaz@ccs.neu.edu Wed Jun 11 23:24:08 1997
>Date: Wed, 11 Jun 1997 23:24:06 -0400 (EDT)
>From: Boaz Patt-Shamir <boaz@ccs.neu.edu>
>To: Karl Lieberherr <lieber@ccs.neu.edu>
>Subject: Re: non-recursive paths
>
>> 
>> a useful concept during adaptive programming is:
>> non-recursive paths from A to B:
>> 
>> Is the following the correct strategy?
>> 
>> A.B * !(A . at-least-one-edge (a1#A + b1#B) . at-least-one-edge B)
>> 
>> -- Karl
>> PS. ! is not, * is intersection. 
>> Can you handle negation efficiently (through interpretation
>> of the traversal graph using tokens)?
>> 
>our only tool for negation is the bypassing clause, or its bigger brother
>the edge predicate. I would write the non-recursive A to B as
>"from A, bypassing A, to-stop B".
>
That is shorter. What is the name space in edge predicates?
Can we only refer to class variables and not to strategy nodes?

What is the difference between the two:

from A . through b1#B . bypassing X through b2#B . bypassing b1#B to C
from A . through b1#B . bypassing X through b2#B . bypassing B    to C

-- Karl

From boaz@ccs.neu.edu Thu Jun 12 09:41:32 1997
From: Boaz Patt-Shamir <boaz@ccs.neu.edu>
Date: Thu, 12 Jun 1997 09:41:31 -0400 (EDT)
To: Karl Lieberherr <lieber@ccs.neu.edu>
Subject: Re: non-recursive paths

 > from A . through b1#B . bypassing X through b2#B . bypassing b1#B to C

This is illegal: the edge predicates are predicates over CLASS GRAPH
edges and nodes; the "b1#B" thing is a strategy graph node.