RESQ_EXISTS_TAC
res_quanLib.RESQ_EXISTS_TAC : term -> tactic
Strips the outermost restricted existential quantifier from the conclusion of a goal.
When applied to a goal A ?- ?x::P. t, the tactic RESQ_EXISTS_TAC
reduces it to a new subgoal A ?- P x' /\ t[x'/x] where x' is a
variant of x chosen to avoid clashing with any variables free in the
goal's assumption list. Normally x' is just x.
A ?- ?x::P. t
====================== RESQ_EXISTS_TAC
A ?- P x' /\ t[x'/x]
Failure
Fails unless the goal's conclusion is a restricted extistential quantification.