nominal app_scope = ()
nominal i0 = ()
nominal i1 = ()
nominal i2 = ()
nominal open_stream = ()
nominal closed_stream = ()

union stream scope cursor state =
    | Stream :: forall scope cursor state. string -> stream scope cursor state

union chunk scope from to =
    | Chunk :: forall scope from to. string -> chunk scope from to

union end_marker scope cursor =
    | EndMarker :: forall scope cursor. string -> end_marker scope cursor

inl append forall scope from to.
    (stream : stream scope from open_stream)
    (chunk : chunk scope from to)
    : stream scope to open_stream =
    match stream, chunk with
    | Stream _, Chunk label => Stream label

inl close forall scope cursor.
    (stream : stream scope cursor open_stream)
    (marker : end_marker scope cursor)
    : stream scope cursor closed_stream =
    match stream, marker with
    | Stream _, EndMarker label => Stream label

inl main () : string =
    inl stream0 : stream app_scope i0 open_stream = Stream "head"
    inl chunk0 : chunk app_scope i0 i1 = Chunk "body"
    inl chunk1 : chunk app_scope i1 i2 = Chunk "tail"
    inl marker : end_marker app_scope i2 = EndMarker "ssr-stream-closed"
    inl stream1 = append stream0 chunk0
    inl stream2 = append stream1 chunk1
    match close stream2 marker with
    | Stream label => label