public static RegExNode Of(RegExNode first, RegExNode second)
{
if (first.RegExType == RegExType.Ranges && second.RegExType == RegExType.Ranges)
{
var r1 = ((RegExNodeRanges)first).Ranges;
var r2 = ((RegExNodeRanges)second).Ranges;
return(new RegExNodeRanges(new[] { r1, r2 }.SelectMany(r => r).ToArray()));
}
return(new RegExNodeUnion(first, second));
}
private void Add(RegExNode node)
{
if (node.RegExType == RegExType.Concat)
{
Expressions.AddRange(((RegExNodeConcat)node).Expressions);
}
else
{
Expressions.Add(node);
}
}
public static RegExNodeRanges Except(RegExNode n1, RegExNode n2)
{
var r1 = n1 as RegExNodeRanges;
var r2 = n2 as RegExNodeRanges;
if ((r1 == null) || (r2 == null))
{
throw new Exception("Invalid expression used in 'except' construct.");
}
var positives = r1.Ranges.SelectMany(range => FindExcepts(range, r2.Ranges)).ToList();
return(new RegExNodeRanges(positives));
}
public RegExNodeExcept(RegExNode e1, RegExNode e2) : base(RegExType.Except)
{
Expression1 = e1;
Expression2 = e2;
}
public RegExNodeRepeat(RegExNode intern, RegExRepeatType regExRepeatType) : base(RegExType.Repeat)
{
Expression = intern;
RegExRepeatType = regExRepeatType;
}
public RegExNodeConcat(RegExNode left, RegExNode right) : base(RegExType.Concat)
{
Add(left);
Add(right);
}
public RegExNodeAccept(RegExNode expression, ushort acceptState) : base(RegExType.Accept)
{
Expression = expression;
AcceptState = acceptState;
}
private RegExNodeUnion(RegExNode first, RegExNode second) : base(RegExType.Union)
{
Add(first);
Add(second);
}