MK_USINGmarkerSyntax.MK_USING : thm -> thm
Encodes a theorem so it can be ASSUME_TAC-ed into a
goal.
A call to MK_USING th encodes th in such a
way that it can safely be the argument to ASSUME_TAC, and
detectable by other tactics operating on the resulting goal as a theorem
that might be worthy of notice.
Fails if the theorem has no hypotheses, is polymorphic, and cannot be
found by reverse lookup in the theorem database (using
DB.revlookup).