From boaz@ccs.neu.edu Wed Aug  6 10:14:04 1997
To: Cristina Lopes <lopes@parc.xerox.com>
cc: lieber@ccs.neu.edu, boaz@ccs.neu.edu, dem@ccs.neu.edu
Subject: Re:  traversals


> 2) you cannot reach arbitrary object paths, which, ultimately, should
>    be the goal; (e.g. a_instance1 b1_instance5 a_instance8 etc.) The
>    only predicate for selection is the history on the types of the
>    traversed objects, which seems to be a weak predicate, and albeit
>    not very common in practice (as you said). 

This is false. Any object path is easily programmable by making the
stratgey graph explicit enough (e.g., let each stratgy edge represent
a single class graph edge by excluding all others using "bypassing").