Merged.

Thanks, Malte! The patch looks good. Do you merge it?

Looks ready to be merged to me. Gabi, do you think it's OK?

https://bitbucket.org/malte/downward/commits/branch/issue280

With the change, the translator succeeds on the given problem. However, the
search component then complains that there is no goal condition. This is
actually correct for this task, and the question is how to best handle these
things. I think this is a separate issue, though. I'll bring it up on the
mailing list.

Uploading the new, modified problem to reproduce the issue (to be used together
with the original domain.pddl).

This is fixed with issue335. However, if you change the goal in the example
problem to

  (:goal (forall (?x)
                 (and
;                  (pred ?x)
;                  (ok ?x)
                  )))

(i.e., comment out the two atoms in the conjunction), the translator fails with
an assertion error:

AssertionError: Condition not normalized

I'm changing the title of this issue to address this other bug.

I don't think it has to be a release blocker, so doesn't have to be marked 1.0.
But of course it would be good to fix it.

The attached task comes from issue163. It
throws an AssertionError ("Negated axiom impossible; cannot deal with that")
which should easily be avoidable for constant predicates.

Should this be marked as a bug for 1.0?