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TAC_PROOF                                                   (Tactical)
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TAC_PROOF : goal * tactic -> thm

SYNOPSIS
Attempts to prove a goal using a given tactic.

KEYWORDS
apply.

DESCRIBE
When applied to a goal-tactic pair {(A ?- t,tac)}, the {TAC_PROOF} function
attempts to prove the goal {A ?- t}, using the tactic {tac}. If it succeeds, it
returns the theorem {A' |- t} corresponding to the goal, where the assumption
list {A'} may be a proper superset of {A} unless the tactic is valid; there
is no inbuilt validity checking.

FAILURE
Fails unless the goal has hypotheses and conclusions all of type {bool},
and the tactic can solve the goal.

SEEALSO
BasicProvers.PROVE, Tactical.VALID.

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