Disallow covariant caps in the lower bound of type members
#19624
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
odersky
requested changes
Feb 15, 2024
|
|
||
| // Check the lower bound of path dependent types. | ||
| // See issue #19330. | ||
| val isTypeParam = t.prefix eq NoPrefix |
Contributor
There was a problem hiding this comment.
isTypeParam is misleading as a name. It could also be a local type definition, that also will lead to a NoPrefix. I'd turn it around and define:
val isMember = t.prefix ne NoPrefix
odersky
requested changes
Feb 15, 2024
odersky
approved these changes
Feb 15, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 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Outdated suggestions cannot be applied.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.
Fixes #19330.
Since when instantiating a type member we do not disallow covariant
caps in the instance, a check is added at the application site to check for covariantcaps in the lower bound of type members to maintain soundness. This check is elided for type parameters since their instances are always checked at the instantiation site.