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LEFT_IMP_EXISTS_CONV                                            (Conv)
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LEFT_IMP_EXISTS_CONV : conv

SYNOPSIS
Moves an existential quantification of the antecedent outwards through an
implication.

KEYWORDS
conversion, quantifier, existential, implication.

DESCRIBE
When applied to a term of the form {(?x.P) ==> Q}, the conversion
{LEFT_IMP_EXISTS_CONV} returns the theorem:

   |- (?x.P) ==> Q = (!x'. P[x'/x] ==> Q)

where {x'} is a primed variant of {x} that does not appear free in
the input term.

FAILURE
Fails if applied to a term not of the form {(?x.P) ==> Q}.

SEEALSO
Conv.FORALL_IMP_CONV, Conv.RIGHT_IMP_FORALL_CONV.

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