public static RegexExpression Create(RegexExpression left, RegexExpression right)
{
var leftMatch = left as RegexMatchSet;
if (leftMatch != null)
{
var rightMatch = right as RegexMatchSet;
if (rightMatch != null)
{
var handle = new RangeSetHandle.Union(false);
handle.Add(leftMatch.Handle);
handle.Add(rightMatch.Handle);
return(new RegexMatchSet(leftMatch.Text + '|' + rightMatch.Text, handle));
}
}
return(new RegexAlternation(left, right));
}
public static RegexMatchSet FromSet(string set)
{
var match = rxSet.Match(set);
if (!match.Success)
{
throw new ArgumentException("Set is invalid", "set");
}
var handle = new RangeSetHandle.Union(match.Groups["neg"].Success);
foreach (Capture capture in match.Groups["letter"].Captures)
{
handle.Add((capture.Value[0] == '\\') ? ParseEscape(capture.Value) : new RangeSetHandle.Static(capture.Value.ToCodepoints().Single()));
}
var from = match.Groups["from"].Captures;
var to = match.Groups["to"].Captures;
Debug.Assert(from.Count == to.Count);
for (var i = 0; i < from.Count; i++)
{
handle.Add(new RangeSetHandle.Static(ParseSingleLetter(from[i].Value), ParseSingleLetter(to[i].Value)));
}
return(new RegexMatchSet(set, handle.Simplify()));
}
