Refute.refute_goal: canonical goal addresses from 1 (renamed from refute_subgoal to clarify change in semantics);
command 'refute': Proof.flat_goal provides standard view on internally structured Isar goal, suitable for (semi)automated tools;
List = FOL +
types list 1
arities list :: (term)term
consts Nil :: "'a list"
Cons :: "['a, 'a list] => 'a list"
end