POP_ASSUM_LIST

Tactical.POP_ASSUM_LIST : (thm list -> tactic) -> tactic

Generates a tactic from the assumptions, discards the assumptions and applies the tactic.

When applied to a function and a goal, POP_ASSUM_LIST applies the function to a list of theorems corresponding to the ASSUMEd assumptions of the goal, then applies the resulting tactic to the goal with an empty assumption list.

    POP_ASSUM_LIST f ({A1,...,An} ?- t) = f [A1 |- A1, ..., An |- An] (?- t)

Failure

Fails if the function fails when applied to the list of ASSUMEd assumptions, or if the resulting tactic fails when applied to the goal with no assumptions.

Comments

There is nothing magical about POP_ASSUM_LIST: the same effect can be achieved by using ASSUME a explicitly wherever the assumption a is used. If POP_ASSUM_LIST is used, it is unwise to select elements by number from the ASSUMEd-assumption list, since this introduces a dependency on ordering.

Example

Suppose we have a goal of the following form:

   {a /\ b, c, (d /\ e) /\ f} ?- t

Then we can split the conjunctions in the assumption list apart by applying the tactic:

   POP_ASSUM_LIST (MAP_EVERY STRIP_ASSUME_TAC)

which results in the new goal:

   {a, b, c, d, e, f} ?- t

Making more delicate use of the assumption list than simply rewriting or using resolution.

See also

Tactical.ASSUM_LIST, Tactical.EVERY_ASSUM, Tactic.IMP_RES_TAC, Tactical.POP_ASSUM, Rewrite.REWRITE_TAC