traverse_ could be on UnorderedFoldable
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Description
Also, we should probably implement traverse_ in terms of foldMap not foldRight
def traverse_[A, B](fa: F[A])(fn: A => G[B])(implicit G: Applicative[G]): G[Unit] =
foldMap(fn.andThen(_.unit))(Applicative.monoid[G, Unit])
foldRight is not the most efficient thing in the world since it leverages Eval (although, it may be that implementation is stack safe and the above is not.
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- Open a pull request that references the issue number.
Research direction
Start by locating the UnorderedFoldable entry point for traverse_ and compare its current foldRight implementation with the proposed foldMap expression. Check whether the foldMap approach preserves stack safety and the expected Applicative behavior; done means the implementation choice is validated and covered by the relevant existing tests.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- scala
- Domain
- tooling
- Issue type
- Refactor
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100