Binary tree inorder traversal, using path to root and left subtrees in Haskell

Alternative implementation of binary tree inorder traversal index function, using path to root and left subtrees of path nodes with R direction in Haskell

code:
https://gist.github.com/evgenii-malov/cca0c241e3df9a46776eddf1f57e84a0

Paths with directions - https://www.youtube.com/watch?v=jCAG76JKIkY

Level order traversal with BFS - https://youtu.be/OibwXW1ssV8
Level order traversall with all paths - https://www.youtube.com/watch?v=4mrBrJw_tVc
Level order traversall with zipwith - https://www.youtube.com/watch?v=q0bFTlmmsJI
Level order traversall with label tree - https://www.youtube.com/watch?v=wE85PTrFiZo
Level order traversal of binary tree with fmap - https://youtu.be/vdN-JZQlq70

Видео Binary tree inorder traversal, using path to root and left subtrees in Haskell канала Evgeniy M