public static TElement Read <TElement>([NotNull] this ILexer <TElement> instance, [NotNull] ITextScanner scanner) where TElement : Element
{
if (instance == null)
{
throw new ArgumentNullException(nameof(instance));
}
if (scanner == null)
{
throw new ArgumentNullException(nameof(scanner));
}
var offset = scanner.Offset;
scanner.StartRecording();
TElement candidate = null;
try
{
var context = scanner.GetContext();
foreach (var element in instance.Read(scanner, context))
{
if (candidate == null)
{
candidate = element;
}
else if (element.Text.Length > candidate.Text.Length)
{
candidate = element;
}
}
if (candidate == null)
{
return(null);
}
scanner.Seek(offset + candidate.Text.Length);
}
finally
{
scanner.StopRecording();
}
return(candidate);
}
public bool MoveNext()
{
if (!initialized)
{
start = scanner.Offset;
scanner.StartRecording();
inner = lexer.ReadImpl(scanner, context).GetEnumerator();
initialized = true;
}
if (scanner.Offset != context.Offset)
{
scanner.Seek(context.Offset);
}
if (!inner.MoveNext())
{
if (scanner.Offset != context.Offset)
{
scanner.Seek(context.Offset);
}
return(false);
}
Current = inner.Current;
return(true);
}
