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CONJUNCTS_THEN2                                             (Thm_cont)
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CONJUNCTS_THEN2 : (thm_tactic -> thm_tactical)

SYNOPSIS
Applies two theorem-tactics to the corresponding conjuncts of a theorem.

KEYWORDS
theorem-tactic, conjunction.

DESCRIBE
{CONJUNCTS_THEN2} takes two theorem-tactics, {f1} and {f2}, and a theorem {t}
whose conclusion must be a conjunction. {CONJUNCTS_THEN2} breaks {t} into two
new theorems, {t1} and {t2} which are {CONJUNCT1} and {CONJUNCT2} of {t}
respectively, and then returns the tactic {f1 t1 THEN f2 t2}. Thus

   CONJUNCTS_THEN2 f1 f2 (A |- l /\ r) =  f1 (A |- l) THEN f2 (A |- r)

so if

   A1 ?- t1                     A2 ?- t2
  ==========  f1 (A |- l)      ==========  f2 (A |- r)
   A2 ?- t2                     A3 ?- t3

then

    A1 ?- t1
   ==========  CONJUNCTS_THEN2 f1 f2 (A |- l /\ r)
    A3 ?- t3




FAILURE
{CONJUNCTS_THEN f} will fail if applied to a theorem whose conclusion is not a
conjunction.

COMMENTS
The system shows the type as {(thm_tactic -> thm_tactical)}.

USES
The construction of complex {tactical}s like {CONJUNCTS_THEN}.

SEEALSO
Thm.CONJUNCT1, Thm.CONJUNCT2, Drule.CONJUNCTS, Tactic.CONJ_TAC,
Thm_cont.CONJUNCTS_THEN2, Thm_cont.STRIP_THM_THEN.

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