Biocaml 0.4-dev : Biocaml_sam.parse_header_line

let parse_header_line tvl =

 find1 `HD tvl "VN" >>= fun version ->

 find01 `HD tvl "SO" >>?~

 parse_sort_order >>= fun sort_order ->

 assert_tags `HD tvl ["VN"; "SO"] >>= fun () ->

 header_line ~version ?sort_order ()