Setting optional parameter (Tag request)

 public class SyncTag : ITag 
    {
    }

public class SyncTagger : TaggerBase<SyncTag>
    {
        public SyncTagger(ICodeDocument document) :
            base("SyncTagger", null, document, true)
        {
        }


public override IEnumerable<TagSnapshotRange<SyncTag>> GetTags(NormalizedTextSnapshotRangeCollection snapshotRanges, object parameter)
{
if (snapshotRanges != null)
            {
                // Loop through the snapshot ranges
                foreach (TextSnapshotRange snapshotRange in snapshotRanges)
                {
                    
                    // Get the text of the snapshot range
                    string text = snapshotRange.Text;

                    //TODO: use object parameter
                    if (text.StartsWith("P"))
                    {

                       // Create a tag
                        SyncTag tag = new SyncTag();

                        // Yield the tag
                        yield return new TagSnapshotRange<SyncTag>(
                            TextSnapshotRange.FromSpan(snapshotRange.Snapshot, snapshotRange.StartOffset, 250), tag);
                    }
                }
            }

}