private IEnumerable <SyntaxTrivia> DescendantTriviaIntoTrivia(TextSpan span, Func <SyntaxNode, bool> descendIntoChildren)
{
using (var stack = new TwoEnumeratorListStack(this, descendIntoChildren))
{
while (stack.IsNotEmpty)
{
switch (stack.PeekNext())
{
case TwoEnumeratorListStack.Which.Node:
SyntaxNodeOrToken value;
if (stack.TryGetNextInSpan(ref span, out value))
{
if (value.IsNode)
{
var nodeValue = value.AsNode();
stack.PushChildren(nodeValue, descendIntoChildren);
}
else if (value.IsToken)
{
var token = value.AsToken();
if (token.HasTrailingTrivia)
{
stack.PushTrailingTrivia(ref token);
}
if (token.HasLeadingTrivia)
{
stack.PushLeadingTrivia(ref token);
}
}
}
break;
case TwoEnumeratorListStack.Which.Trivia:
// yield structure nodes and enumerate their children
SyntaxTrivia trivia;
if (stack.TryGetNext(out trivia))
{
// PERF: Push before yield return so that "trivia" is 'dead' after the yield
// and therefore doesn't need to be stored in the iterator state machine. This
// saves a field.
if (trivia.HasStructure)
{
var structureNode = trivia.GetStructure();
stack.PushChildren(structureNode, descendIntoChildren);
}
if (IsInSpan(ref span, trivia.FullSpan))
{
yield return(trivia);
}
}
break;
}
}
}
}
private IEnumerable<SyntaxTrivia> DescendantTriviaIntoTrivia(TextSpan span, Func<SyntaxNode, bool> descendIntoChildren)
{
using (var stack = new TwoEnumeratorListStack(this, descendIntoChildren))
{
while (stack.IsNotEmpty)
{
switch (stack.PeekNext())
{
case TwoEnumeratorListStack.Which.Node:
SyntaxNodeOrToken value;
if (stack.TryGetNextInSpan(ref span, out value))
{
if (value.IsNode)
{
var nodeValue = value.AsNode();
stack.PushChildren(nodeValue, descendIntoChildren);
}
else if (value.IsToken)
{
var token = value.AsToken();
if (token.HasTrailingTrivia)
{
stack.PushTrailingTrivia(ref token);
}
if (token.HasLeadingTrivia)
{
stack.PushLeadingTrivia(ref token);
}
}
}
break;
case TwoEnumeratorListStack.Which.Trivia:
// yield structure nodes and enumerate their children
SyntaxTrivia trivia;
if (stack.TryGetNext(out trivia))
{
// PERF: Push before yield returnsca so that "trivia" is 'dead' after the yield
// and therefore doesn't need to be stored in the iterator state machine. This
// saves a field.
if (trivia.HasStructure)
{
var structureNode = trivia.GetStructure();
stack.PushChildren(structureNode, descendIntoChildren);
}
if (IsInSpan(ref span, trivia.FullSpan))
{
yield return trivia;
}
}
break;
}
}
}
}