CONJUNCTS_THEN2 : thm_tactic -> thm_tactic -> thm_tactic

SYNOPSIS

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

DESCRIPTION

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 CONDITIONS

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

USES

The construction of complex tacticals like CONJUNCTS_THEN.