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LEFT_OR_EXISTS_CONV                                             (Conv)
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LEFT_OR_EXISTS_CONV : conv

SYNOPSIS
Moves an existential quantification of the left disjunct outwards through a
disjunction.

KEYWORDS
conversion, quantifier, existential, disjunction.

DESCRIBE
When applied to a term of the form {(?x.P) \/ Q}, the conversion
{LEFT_OR_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.EXISTS_OR_CONV, Conv.OR_EXISTS_CONV, Conv.RIGHT_OR_EXISTS_CONV.

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