public IntSet Visit(RepeatNode node, int posOffset)
{
int innerPosCount = PosCounter.Of(node.Inner);
var result = SparseIntSetType.Instance.Mutable();
// Traverse optional + last repetitions
int compilationCount = node.InnerCompilationCount;
int minCount = Math.Max(node.MinCount, 1);
for (int i = minCount - 1; i != compilationCount; ++i)
{
int offset = posOffset + innerPosCount * i;
result.AddAll(node.Inner.Accept(this, offset));
}
bool isInnerNullable = node.Inner.Accept(NullableGetter.Instance);
if (isInnerNullable)
{
// Traverse forced but nullable repetitions
for (int i = 0; i != node.MinCount; ++i)
{
int offset = posOffset + innerPosCount * i;
result.AddAll(node.Inner.Accept(this, offset));
}
}
return(result.CompleteAndDestroy());
}
public void FillFollowPos(
int posOffset,
List <RegularPositionInfo> positions,
IEnumerable <AstNode> children)
{
int leftOffset = posOffset;
for (int i = 1; i < children.Count(); ++i)
{
var left = children.ElementAt(i - 1);
int rightOffset = leftOffset + PosCounter.Of(left);
foreach (int leftPos in lastPosGetter.LastPos(posOffset, children.Take(i)))
{
IntSet firstPos = firstPosGetter.FirstPos(rightOffset, children.Skip(i));
positions[leftPos].FollowPos.AddAll(firstPos);
}
leftOffset = rightOffset;
}
int offset = posOffset;
foreach (var node in children)
{
node.Accept(this, offset);
offset += PosCounter.Of(node);
}
}
public object Visit(OrNode node, int posOffset)
{
int offset = posOffset;
foreach (var child in node.Children)
{
child.Accept(this, offset);
offset += PosCounter.Of(child);
}
return(this);
}
public IntSet Visit(OrNode node, int posOffset)
{
var result = SparseIntSetType.Instance.Mutable();
int offset = posOffset;
foreach (var child in node.Children)
{
result.AddAll(child.Accept(this, offset));
offset += PosCounter.Of(child);
}
return(result);
}
public object Visit(RepeatNode node, int posOffset)
{
FillFollowPos(
posOffset,
positions,
Enumerable.Repeat(node.Inner, node.InnerCompilationCount));
if (node.MaxCount == int.MaxValue)
{
FillFollowPosClosure(
posOffset + node.MinCount * PosCounter.Of(node.Inner),
node.Inner);
}
return(this);
}
public IntSet LastPos(int posOffset, IEnumerable <AstNode> seq)
{
var result = SparseIntSetType.Instance.Mutable();
int offset = posOffset + seq.Sum(node => PosCounter.Of(node));
foreach (var node in Enumerable.Reverse(seq))
{
offset -= PosCounter.Of(node);
result.AddAll(node.Accept(this, offset));
if (!node.Accept(NullableGetter.Instance))
{
break;
}
}
return(result.CompleteAndDestroy());
}
public IntSet FirstPos(int posOffset, IEnumerable <AstNode> seq)
{
var result = SparseIntSetType.Instance.Mutable();
int offset = posOffset;
foreach (var node in seq)
{
result.AddAll(node.Accept(this, offset));
if (!node.Accept(NullableGetter.Instance))
{
break;
}
offset += PosCounter.Of(node);
}
return(result.CompleteAndDestroy());
}