File: PRESIMP_CONV.doc

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\DOC PRESIMP_CONV

\TYPE {PRESIMP_CONV : conv}

\SYNOPSIS
Applies basic propositional simplifications and some miniscoping.

\DESCRIBE
The conversion {PRESIMP_CONV} applies various routine simplifications to
Boolean terms involving constants, e.g. {p /\ T <=> p}. It also tries to push
universal quantifiers through conjunctions and existential quantifiers through
disjunctions, e.g. {(?x. p[x] \/ q[x]) <=> (?x. p[x]) \/ (?x. q[x])}
(``miniscoping'') but does not transform away other connectives like
implication that would allow it do do this more completely.

\FAILURE
Never fails.

\EXAMPLE
{
  # PRESIMP_CONV `?x. x = 1 /\ y = 1 \/ F \/ T /\ y = 2`;;
  val it : thm =
    |- (?x. x = 1 /\ y = 1 \/ F \/ T /\ y = 2) <=>
       (?x. x = 1) /\ y = 1 \/ y = 2
}

\USES
Useful as an initial simplification before more substantial normal form
conversions.

\SEEALSO
CNF_CONV, DNF_CONV, NNF_CONV, PRENEX_CONV, SKOLEM_CONV.

\ENDDOC