fix(#19402): error message for missing using in given params #19496
Conversation
This file contains 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
`given`-s can't have non-implicit arguments, but when users forget
adding a `using` modifier to given parameters, it showed unfriendly error
message; "only classes can have declared but undefined members".
The `termParamClauses` parser is aware of the owner of parameters and it raises
a syntax error when parameters in given definition do not have `using` modifier with clear reason,
but `in.token == LPAREN && in.lookahead.isIdent(nme.using)` in
Parsers.scala was too strict to delegate parameter clause handling to `termParamClauses`.
Note:
This change requires tests/neg/i8150.check to be updated because the original
test starts failing due to the syntax error rather than "refinement cannot be `given`" error.
`type T = {given A with A}` in i8150.check confirms that a valid given definition
in RHS of type alias still raises the original error; "refinement cannot be `given`" error.
|
This will clash with the proposed syntax changes for type classes, which would make the change unnecessary. I therefore like to put this on hold until the fate of these syntax changes is decided. |
|
The syntax changes are now all stabilized. So @i10416, if you want to pick this up again, now it's all clear. |
|
Thank you for reminder! |
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Outdated suggestions cannot be applied.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.
close #19402
given-s can't have non-implicit arguments, but when users forget adding ausingmodifier to given parameters, it showed unfriendly error message; "only classes can have declared but undefined members".The
termParamClausesparser is aware of the owner of parameters and it raises a syntax error when parameters in given definition do not haveusingmodifier with clear reason, but the conditionin.token == LPAREN && in.lookahead.isIdent(nme.using)in Parsers.scala was too strict to delegate parameter clause handling totermParamClauses.Note:
This change requires tests/neg/i8150.check to be updated because the original test starts failing due to the syntax error rather than "refinement cannot be
given" error.type T = {given A with A}in i8150.check confirms that a valid given definition in RHS of type alias still raises the original error; "refinement cannot begiven" error.