File: FORALL_UNWIND_CONV.doc

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\DOC FORALL_UNWIND_CONV

\TYPE {FORALL_UNWIND_CONV : term -> thm}

\SYNOPSIS
Eliminates universally quantified variables that are equated to something.

\KEYWORDS
conversion.

\DESCRIBE
The conversion {FORALL_UNWIND_CONV}, applied to a formula with one or more 
universal quantifiers around an implication, eliminates any quantifiers where 
the antecedent of the implication contains a conjunct equating its variable to
some other term (with that variable not free in it).

\FAILURE
{FORALL_UNWIND_CONV tm} fails if {tm} is not reducible according to that
description.

\EXAMPLE
{
  # FORALL_UNWIND_CONV
     `!a b c d. a + 1 = b /\ b + 1 = c + 1 /\ d = e ==> a + b + c + d + e = 2`;;
  val it : thm =
    |- (!a b c d.
            a + 1 = b /\ b + 1 = c + 1 /\ d = e ==> a + b + c + d + e = 2) <=>
       (!a c. (a + 1) + 1 = c + 1 ==> a + (a + 1) + c + e + e = 2)
  # FORALL_UNWIND_CONV `!a b c. a = b /\ b = c ==> a + b = b + c`;;
  val it : thm =
    |- (!a b c. a = b /\ b = c ==> a + b = b + c) <=> (!c. c + c = c + c)
}

\SEEALSO
UNWIND_CONV.

\ENDDOC