Differentiate Scala 2 and Scala 3 wildcard identifier names#9614
Merged
lrytz merged 1 commit intoscala:2.13.xfrom May 10, 2021
Merged
Differentiate Scala 2 and Scala 3 wildcard identifier names#9614lrytz merged 1 commit intoscala:2.13.xfrom
lrytz merged 1 commit intoscala:2.13.xfrom
Conversation
This change names wildcards written with Scala 3 `?` syntax with `?$N` pattern instead of `_$N` used for Scala 2 wildcards There are two reasons for it: - To allow `kind-projector` to implement Scala 3 underscore syntax for type lambdas by transforming old-style underscores, but leaving Scala 3 underscores intact - To show a mildly more relevant error message, since a wildcard introduced by `?` will now also have a name with `?` in the error message
Contributor
Author
|
This change is required together with #9605 to implement typelevel/kind-projector#188 |
lrytz
approved these changes
May 10, 2021
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This change names wildcards written with Scala 3
?syntax with?$Npattern instead of_$Nused for Scala 2 wildcardsThere are two reasons for it:
kind-projectorto implement Scala 3 underscore syntax for type lambdas by transforming old-style underscores, but leaving Scala 3 underscores intact?will now also have a name with?in the error messageSee also:
_as a placeholder and?as wildcard? typelevel/kind-projector#120