walk* of an empty set overflows the stack

Question

I noticed this issue when asserting a relation with an empty set in it in the new pldb stuff, the minimal case I have is (walk* empty-s #{})

Answer 1

Comment made by: norman

Here's an update that allows sets to be uses as terms and correctly walks sets. It does not do unification of one set with another, which is a much harder problem.

Answer 2

Comment made by: dnolen

The fact that equal sets don't unify is problematic. That at least should work. Sets with logic vars in them should throw. Unification (assignment) of a set to a logic var should work.

Answer 3

Reference: https://clojure.atlassian.net/browse/LOGIC-154 (reported by hiredman)