//also used by XPathPatternBuilder
public static QilNode PredicateToBoolean(QilNode predicate, XPathQilFactory f, IXPathEnvironment env)
{
// Prepocess predicate: if (predicate is number) then predicate := (position() == predicate)
if (!f.IsAnyType(predicate))
{
if (predicate.XmlType.TypeCode == XmlTypeCode.Double)
{
predicate = f.Eq(env.GetPosition(), predicate);
}
else
{
predicate = f.ConvertToBoolean(predicate);
}
}
else
{
QilIterator i;
predicate = f.Loop(i = f.Let(predicate),
f.Conditional(f.IsType(i, T.Double),
f.Eq(env.GetPosition(), f.TypeAssert(i, T.DoubleX)),
f.ConvertToBoolean(i)
)
);
}
return(predicate);
}
private QilNode LogicalOperator(XPathOperator op, QilNode left, QilNode right)
{
Debug.Assert(op == XPathOperator.Or || op == XPathOperator.And);
left = _f.ConvertToBoolean(left);
right = _f.ConvertToBoolean(right);
return(
op == XPathOperator.Or ? _f.Or(left, right) :
/*default*/ _f.And(left, right)
);
}