pub fn from_block(
  bytes: BitArray,
  hash_sha256: fn(BitArray) -> fn(fn(BitArray) -> t) -> t,
) -> fn(fn(v1.Cid) -> t) -> t

pub fn from_tree(
  source: #(tree.Expression(a), a),
  hash_sha256: fn(BitArray) -> fn(fn(BitArray) -> t) -> t,
) -> fn(fn(v1.Cid) -> t) -> t