test_blending.ml

let b =
  let open PrintBox in
  tree
    (frame @@ text "root")
    [
      frame @@ text "child 1";
      text "child 2";
      frame
      @@ tree empty
           [ tree (frame @@ text "header 3") [ frame @@ text "subchild 3" ] ];
      tree empty
        [ tree (frame @@ text "header 4") [ frame @@ text "subchild 4" ] ];
      frame @@ text "child 5";
      frame
      @@ tree
           (frame @@ text "header 6")
           [ tree (frame @@ text "child 6") [ frame @@ text "subchild 6" ] ];
    ]

let () = print_endline @@ PrintBox_text.to_string b