blockToMan opts (OrderedList attribs items) = do
  let markers = take (length items) $ orderedListMarkers attribs  
  let indent = 1 + (maximum $ map length markers)
  contents <- mapM (\(num, item) -> orderedListItemToMan opts num indent item) $
              zip markers items  
  return (vcat contents)
blockToMan opts (OrderedList attribs items) = do
  let markers = take (length items) $ orderedListMarkers attribs  
  let indent = 1 + (maximum $ map length markers)
  contents <- mapM (\(num, item) -> orderedListItemToMan opts num indent item) $
              zip markers items  
  return (vcat contents)
blockToMan opts (OrderedList attribs items) = do
  let markers = take (length items) $ orderedListMarkers attribs  
  let indent = 1 + (maximum $ map length markers)
  contents <- mapM (\(num, item) -> orderedListItemToMan opts num indent item) $
              zip markers items  
  return (vcat contents)