withstate.kt

 override fun invalidate(): Unit = withState(postViewModel) {
        binding.progess.isVisible = it.post is Loading
        when (it.post) {
            is Success -> {
                binding.progess.visibility = View.GONE
                adapter.submitList(it.post.invoke())
            }
            is Fail -> {
                Toast.makeText( requireContext(), "An error occured", Toast.LENGTH_SHORT).show()
                Log.e("message", it.post.error.localizedMessage)
            }
        }
    }