protected internal virtual Expression VisitOperatorAnd(OperatorAnd node)
{
var left = Visit(node.Left);
var right = Visit(node.Right);
if (node.Left == left && node.Right == right)
{
return node;
}
else
{
return new OperatorAnd(left, right);
}
}
protected internal virtual Expression VisitOperatorAnd(OperatorAnd node)
{
var left = Visit(node.Left);
var right = Visit(node.Right);
if (node.Left == left && node.Right == right)
{
return(node);
}
else
{
return(new OperatorAnd(left, right));
}
}
protected internal override Expression VisitOperatorAnd(OperatorAnd node)
{
// Both operands must be in DNF
var left = Visit(node.Left);
var right = Visit(node.Right);
// Form Cartesian product of terms
Expression[] leftterms, rightterms;
if (left is OperatorOr)
{
leftterms = ((OperatorOr)left).EnumerateTerms().ToArray();
}
else
{
leftterms = new Expression[] { left };
}
if (right is OperatorOr)
{
rightterms = ((OperatorOr)right).EnumerateTerms().ToArray();
}
else
{
rightterms = new Expression[] { right };
}
Expression res = null;
for (int i = 0; i < leftterms.Length; i++)
{
for (int j = 0; j < rightterms.Length; j++)
{
var t = new OperatorAnd(leftterms[i], rightterms[j]);
if (res == null)
{
res = t;
}
else
{
res = new OperatorOr(t, res);
}
}
}
return(res);
}
protected internal override Expression VisitOperatorOr(OperatorOr node)
{
// Both operands must be in CNF
var left = Visit(node.Left);
var right = Visit(node.Right);
// Form Cartesian product of terms
Expression[] leftterms, rightterms;
if (left is OperatorAnd)
{
leftterms = ((OperatorAnd)left).EnumerateTerms().ToArray();
}
else
{
leftterms = new Expression[] { left };
}
if (right is OperatorAnd)
{
rightterms = ((OperatorAnd)right).EnumerateTerms().ToArray();
}
else
{
rightterms = new Expression[] { right };
}
Expression res = null;
for (int i = 0; i < leftterms.Length; i++)
{
for (int j = 0; j < rightterms.Length; j++)
{
var t = new OperatorOr(leftterms[i], rightterms[j]);
if (res == null)
{
res = t;
}
else
{
res = new OperatorAnd(t, res);
}
}
}
return res;
}
private void EnumerateTermsInternal(OperatorAnd node, Stack<Expression> stack)
{
if (node.Left is OperatorAnd)
{
EnumerateTermsInternal((OperatorAnd)node.Left, stack);
}
else
{
stack.Push(node.Left);
}
if (node.Right is OperatorAnd)
{
EnumerateTermsInternal((OperatorAnd)node.Right, stack);
}
else
{
stack.Push(node.Right);
}
}
private void EnumerateTermsInternal(OperatorAnd node, Stack <Expression> stack)
{
if (node.Left is OperatorAnd)
{
EnumerateTermsInternal((OperatorAnd)node.Left, stack);
}
else
{
stack.Push(node.Left);
}
if (node.Right is OperatorAnd)
{
EnumerateTermsInternal((OperatorAnd)node.Right, stack);
}
else
{
stack.Push(node.Right);
}
}
