from ranges import quicly_ranges_t

type
  quicly_sendstate_t* {.bycopy.} = object
    acked*: quicly_ranges_t
    pending*: quicly_ranges_t
    size_inflight*: uint64
    final_size*: uint64

  quicly_sendstate_sent_t* {.bycopy.} = object
    start*: uint64
    `end`*: uint64

proc quicly_sendstate_is_open*(state: ptr quicly_sendstate_t): cint
                              {.cdecl, importc.}