public virtual SyntaxTriviaList VisitList(SyntaxTriviaList list)
{
var count = list.Count;
if (count != 0)
{
SyntaxTriviaListBuilder alternate = null;
var index = -1;
foreach (var item in list)
{
index++;
var visited = VisitListElement(item);
//skip the null check since SyntaxTrivia is a value type
if (visited != item && alternate == null)
{
alternate = new SyntaxTriviaListBuilder(count);
alternate.Add(list, 0, index);
}
if (alternate != null && visited != null)
{
alternate.Add(visited);
}
}
if (alternate != null)
{
return(alternate.ToList());
}
}
return(list);
}
private static SyntaxNode CreateNode(SyntaxTrivia[] trivias)
{
if (trivias == null)
{
return(null);
}
var builder = new SyntaxTriviaListBuilder(trivias.Length);
builder.Add(trivias);
return(builder.ToList().Node);
}
private static void ClearAndFreeBuilder(SyntaxTriviaListBuilder builder)
{
// It's possible someone might create a list with a huge amount of trivia
// in it. We don't want to hold onto such items forever. So only cache
// reasonably sized lists. In IDE testing, around 99% of all trivia lists
// were 16 or less elements.
const int MaxBuilderCount = 16;
if (builder.Count <= MaxBuilderCount)
{
builder.Clear();
s_builderPool.Free(builder);
}
}
/// <summary>
/// Creates a list of trivia.
/// </summary>
/// <param name="trivias">A sequence of trivia.</param>
public SyntaxTriviaList(IEnumerable <SyntaxTrivia> trivias)
: this(SyntaxTriviaListBuilder.Create(trivias).Node, 0, 0)
{
}
