/// <summary>
///
/// </summary>
/// <param name="name"></param>
/// <param name="text"></param>
/// <remarks>
/// When parsing text, it is always assumed as the start that the rule is an
/// alternating group of groups, and when a grouping token is encountered the same
/// is assumed. The simplify method is called at the end
/// </remarks>
public void AddRule(string name, string text)
{
int matchedGroup;
Grouping currentAlternation = new Grouping(Alternation.Instance)
{
ProductionName = name
};
Grouping currentGroup = new Grouping(Concatenation.Instance);
currentAlternation.Add(currentGroup);
foreach (Match match in ruleTokenizer.Matches(text))
{
matchedGroup = match.Groups.Cast <System.Text.RegularExpressions.Group>()
.Select((g, i) => new { Group = g, Index = i })
.FirstOrDefault(g => g.Group.Success && g.Index > 0).Index;
switch (matchedGroup)
{
case 1:
currentGroup.Add(new Referrer(match.Value));
break;
case 2:
currentGroup.Add(Literal.FromQuoted(match.Value));
break;
case 3:
switch (match.Value)
{
case "(":
currentAlternation = new Grouping(Alternation.Instance);
currentGroup.Add(currentAlternation);
currentGroup = new Grouping(Concatenation.Instance);
currentAlternation.Add(currentGroup);
break;
case ")":
if (currentAlternation.IsException)
{
currentGroup = currentAlternation.Parent;
currentAlternation = currentGroup.Parent;
}
currentGroup = currentAlternation.Parent;
currentAlternation = currentGroup.Parent;
break;
case "|":
if (currentAlternation.IsException)
{
currentGroup = currentAlternation.Parent;
currentAlternation = currentGroup.Parent;
}
currentGroup = new Grouping(Concatenation.Instance);
currentAlternation.Add(currentGroup);
break;
case "-":
currentAlternation = new Grouping(Alternation.Instance)
{
IsException = true
};
currentGroup.Add(currentAlternation);
currentGroup = new Grouping(Concatenation.Instance);
currentAlternation.Add(currentGroup);
break;
}
break;
case 4:
currentGroup.Last().Quantifier = match.Value;
break;
case 6:
throw new Exception(String.Format("Invalid token \"{0}\" at {1}", match.Value,
match.Index));
}
}
Add(Simplify(currentAlternation));
}
