Better error message for ifs that miss an else branch #8672
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
ryanberckmans
added a commit
to ryanberckmans/scala-helpful-compiler-errors
that referenced
this pull request
Apr 5, 2020
smarter
reviewed
Apr 6, 2020
| errorTree(tree, TypeMismatch(treeTp, pt, implicitFailure.whyNoConversion)) | ||
| def missingElse = tree match | ||
| case If(_, _, elsep @ Literal(Constant(()))) if elsep.span.isSynthetic => | ||
| "\nMaybe you are missing an else part for the conditional?" |
There was a problem hiding this comment.
If the Unit in the error message is the confusing part, maybe we could explain that:
Suggested change
| "\nMaybe you are missing an else part for the conditional?" | |
| "\nNote: an `if` without a corresponding `else` will always have type `Unit`" |
Not sure if that's better.
There was a problem hiding this comment.
I think the single line is enough of a hint. An intelligent reader will connect the dots.
It's cleaner to handle the choice what addendum to print in the message itself.
smarter
approved these changes
Apr 6, 2020
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Outdated suggestions cannot be applied.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.
Motivated by https://github.com/ryanberckmans/scala-helpful-compiler-errors