Fixed bug that caused proof of induction rule to fail for inductive sets with trivial introduction rules such as "x : S ==> x : S".
Fixed bug that caused proof of induction rule to fail
for inductive sets with trivial introduction rules
such as "x : S ==> x : S".

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle