\DOC FRONT_CONJ_CONV
\TYPE {FRONT_CONJ_CONV: term list -> term -> thm}
\SYNOPSIS
Moves a specified conjunct to the beginning of a conjunction.
\KEYWORDS
conversion, conjunction, associative, commutative.
\DESCRIBE
Given a list of boolean terms {[t1,...,t,...,tn]} and a term {t} which
occurs
in the list, {FRONT_CONJ_CONV} returns:
{
|- (t1 /\ ... /\ t /\ ... /\ tn) = (t /\ t1 /\ ... /\ tn)
}
That is, {FRONT_CONJ_CONV} proves that {t} can be moved to the
`front' of a conjunction of several terms.
\FAILURE
{FRONT_CONJ_CONV [t1,...,tn] t} fails if {t} does not occur in the list
{[t1,...,tn]} or if any of {t1}, ..., {tn} do not have type {bool}.
\COMMENTS
This is not a true conversion, so perhaps it ought to be called something
else.
\ENDDOC