// Step 3
void Process(Rule rule)
{
// Create $result variable if it was used
bool usingResult = _data.OtherReferences.ContainsKey(_resultId) || _data.ProperLabels.TryGetValue(_result, false);
if (usingResult && rule.ReturnType != null)
{
_data.ProperLabels[_result] = true;
var type = rule.ReturnType;
_newVarInitializers[_result] = Pair.Create(type, _codeGen.MakeInitializedVarDecl(type, false, _result));
}
Visit(rule.Pred);
if (_newVarInitializers.Count != 0)
{
var decls = _newVarInitializers.OrderBy(p => p.Key.Name).Select(p => p.Value.B);
LNode decls2 = F.Call(S.Splice, decls);
rule.Pred.PreAction = Pred.MergeActions(decls2, rule.Pred.PreAction);
if (usingResult)
{
rule.Pred.PostAction = Pred.MergeActions(rule.Pred.PostAction, F.Call(S.Return, _resultId));
}
}
}
Pred ArgsToSeq(LNode expr, Context ctx)
{
List <object> objs = expr.Args.Select(node => AutoNodeToPred(node, ctx)).ToList();
Seq seq = new Seq(expr);
LNode action = null;
bool error = false;
for (int i = 0; i < objs.Count; i++)
{
if (objs[i] is LNode)
{
var code = (LNode)objs[i];
if ((ctx == Context.And || ctx == Context.GateLeft) && !error)
{
error = true;
_sink.Write(Severity.Error, objs[i], ctx == Context.And ?
"Cannot use an action block inside an '&' or '!' predicate; these predicates are for prediction only." :
"Cannot use an action block on the left side of a '=>' gate; the left side is for prediction only.");
}
action = Pred.MergeActions(action, code);
}
else // Pred
{
Pred pred = (Pred)objs[i];
pred.PreAction = Pred.MergeActions(action, pred.PreAction);
action = null;
seq.List.Add(pred);
}
}
if (action != null)
{
seq.PostAction = action;
}
if (seq.List.Count == 1)
{
var contents = seq.List[0];
contents.PreAction = Pred.MergeActions(seq.PreAction, contents.PreAction);
contents.PostAction = Pred.MergeActions(seq.PostAction, contents.PostAction);
return(contents);
}
return(seq);
}
public Seq(Pred one, Pred two, LNode basis = null) : base(basis)
{
if (one is Seq)
{
PreAction = one.PreAction;
List.AddRange((one as Seq).List);
if (List.Count > 0)
{
var last = List[List.Count - 1];
last.PostAction = Pred.MergeActions(last.PostAction, one.PostAction);
}
else
{
PreAction = Pred.MergeActions(PreAction, one.PostAction);
}
}
else
{
List.Add(one);
}
if (two is Seq)
{
if (List.Count > 0)
{
var last = List[List.Count - 1];
last.PostAction = Pred.MergeActions(last.PostAction, two.PreAction);
}
else
{
PreAction = Pred.MergeActions(PreAction, two.PreAction);
}
List.AddRange((two as Seq).List);
PostAction = Pred.MergeActions(PostAction, two.PostAction);
}
else
{
List.Add(two);
}
}