public Grammar AddLanguage(string filename)
{
var currentScopes = new List<Scope>();
Rule rule = null;
foreach (var line in File.ReadAllLines(filename))
{
try
{
var tokens = GetTokens(line).ToArray();
if (tokens.Length == 0) continue;
if (tokens[0].First == GrammarToken.Pattern)
{
if (tokens.Length != 3 || tokens[1].First != GrammarToken.Arrow || tokens[2].First != GrammarToken.ScopeName)
throw new InvalidDataException("Expected `pattern -> scopename`");
if (currentScopes.Count == 0) throw new InvalidDataException("Rule without context");
rule = new Rule(tokens[0].Second, tokens[2].Second);
foreach (var scope in currentScopes)
scope.AddRule(rule);
}
if (tokens[0].First == GrammarToken.Keyword)
{
if (tokens[0].Second == "in")
{
if (tokens.Length != 2 || tokens[1].First != GrammarToken.ScopeName)
throw new InvalidDataException("Expected `scopename` to follow `in`");
currentScopes = tokens[1].Second.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries)
.Select(x => scopes[x.Trim()]).ToList();
}
else if (tokens[0].Second == "enter:")
{
if (rule == null)
throw new InvalidDataException("`enter` action without rule");
rule.SetAction(RuleAction.Push, tokens[1].Second);
}
else if (tokens[0].Second == "leave:")
{
if (rule == null)
throw new InvalidDataException("`leave` action without rule");
rule.SetAction(tokens[1].Second == "after" ? RuleAction.PopAfter : RuleAction.PopBefore);
}
else
{
var capnum = tokens[0].Second.Substring(0, tokens[0].Second.Length - 1);
int n;
if (!int.TryParse(capnum, out n))
throw new InvalidDataException("Unrecognized option: {0}".F(tokens[0].Second));
rule.SetCaptureScope(n, tokens[1].Second);
}
}
}
catch (Exception e) { errors.Add(Pair.New(filename, e.Message)); }
}
return this;
}
public void AddRule(Rule r)
{
rules.Add(r);
}
