Weaken some Alternative constraints in OneAnd
#4739
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
kory33
commented
Apr 20, 2025
| @@ -123,8 +123,21 @@ final case class OneAnd[F[_], A](head: A, tail: F[A]) { | |||
| s"OneAnd(${A.show(head)}, ${FA.show(tail)})" | |||
| } | |||
|
|
|||
| private[data] trait OneAndBinCompat0[F[_], A] { | |||
There was a problem hiding this comment.
[question] Is this the right way to pass the MiMa check for a case class modification?
I saw #3997 (comment) and thought that this was the (only) way, but I could not find any other place that defines a similar bincompat trait (other than ValidatedFunctionsBinCompat0, which patches the companion rather than the Validated class itself).
kory33
commented
Apr 20, 2025
| val head: A | ||
| val tail: F[A] | ||
|
|
||
| @deprecated("Kept for binary compatibility", "2.14.0") |
There was a problem hiding this comment.
[question] Is since = "2.14.0" specification appropriate (is that the next cats version)? Or do I just not need @deprecated at all since it's private[data]?
|
Oh, I thought I made the bincompat check pass but I didn't! I'll try to fix it. |
the situation looks very similar to https://github.com/typelevel/cats/pull/4055/files#r760450709.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Currently, the
unwrapandcombinemethods inOneAnd, as well asSemigroupK/Semigroupinstance haveAlternativeas a bound for the typeF[_]of collection-like component.This pull request weakens this constraint to
F[_]: NonEmptyAlternative.Context
The change allows one to
unwrapOneOf[NonEmptyList, A]intoNonEmptyList[A]. At first glance puttingNonEmptyListinOneOfsounds a bit weird, but I think they are natural choices for situations when one wants to describe a collection of2..Nitems (this occurred to me while describing "duplicate inputs error" in a validation logic, where the errorcase classhad a length ≥2 list of input indices containing duplicates).I think this
weakeninggeneralization makes sense since, intuitively, none of the aforementioned methods interact with theempty: F[Nothing]aspect of the collection: they only combine collections (SemigroupK) or inject an element into the collection (NonEmptyAlternative).