public virtual LNode CallRule(RuleRef rref, bool recognizerMode)
{
Rule target = rref.Rule;
var @params = rref.Params;
if (recognizerMode)
{
target = target.MakeRecognizerVersion();
// Allow recognizers to take fewer arguments than the normal rule
// by truncating argument(s) at the call site.
int maxArgCount = target.Basis.CallsMin(S.Fn, 3) ? target.Basis.Args[2].ArgCount : 0;
if (@params.Count > maxArgCount)
{
@params = @params.First(maxArgCount);
}
}
LNode call = F.Call(target.Name, @params);
if (recognizerMode)
{
return(F.Call(S.If, F.Call(S.Not, call), F.Call(S.Return, F.@false)));
}
else
{
return(rref.AutoSaveResult(call));
}
}
public virtual LNode CallTryRecognizer(RuleRef rref, int lookahead)
{
Rule target = rref.Rule;
target = target.MakeRecognizerVersion();
LNode name = target.TryWrapperName;
var @params = rref.Params;
return(F.Call(name, @params.Insert(0, F.Literal(lookahead))));
}
private static void ApplyRuleOptions(ref LNode node, Rule rule, IMessageSink sink)
{
node = node.WithAttrs(node.Attrs.Select(attr => {
switch (attr.Name.Name)
{
case "fullLLk":
case "FullLLk":
ReadOption <bool>(sink, attr, v => rule.FullLLk = v, true);
break;
case "#private":
case "private":
case "priv":
case "Private":
ReadOption <bool>(sink, attr, v => rule.IsPrivate = v, true);
break;
case "token":
case "Token":
ReadOption <bool>(sink, attr, v => rule.IsToken = v, true);
break;
case "start":
case "Start":
ReadOption <bool>(sink, attr, v => rule.IsStartingRule = v, true);
break;
case "#extern":
case "extern":
case "Extern":
ReadOption <bool>(sink, attr, v => rule.IsExternal = v, true);
break;
case "k":
case "K":
case "LL":
ReadOption <int>(sink, attr, k => rule.K = k, null);
break;
case "recognizer":
case "Recognizer":
LNode sig = null;
if (attr.ArgCount == 1)
{
sig = attr.Args[0];
if (sig.Calls(S.Braces, 1))
{
sig = sig.Args[0];
}
// TODO: we need a way to invoke all applicable macros at a particular location
// e.g. "public Foo()::bool;" is not supported by def() alone.
sig = LeMP.Prelude.Les.Macros.def(sig, sink) ?? sig;
}
if (sig != null && sig.CallsMin(S.Fn, 3))
{
rule.MakeRecognizerVersion(sig).TryWrapperNeeded();
}
else
{
sink.Write(Severity.Error, sig, "'recognizer' expects one parameter, a method signature.");
}
break;
default:
return(attr);
}
return(null);
}).WhereNotNull().ToArray());
}
