typelevel / typelevel/cats

`Either.catchOnly` and `-Yexplicit-nulls` are not playing well together

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Scala
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Description

Hi,

Either.catchOnly does not seem usable with -Yexplicit-nulls enabled on Scala 3.5.2:

[error] -- [E057] Type Mismatch Error: /.../CaseAppParsers.scala:18:17 
[error] 18 |      .catchOnly[NumberFormatException](Duration(s))
[error]    |                 ^
[error]    |Type argument NumberFormatException does not conform to lower bound Null
[error]    |
[error]    | longer explanation available when compiling with `-explain`
[error] two errors found

Is there something that can be done at the library level?

Thanks

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Research direction

Reproduce the Scala 3.5.2 explicit-nulls failure from CaseAppParsers.scala at line 18, focusing on the Either.catchOnly[NumberFormatException] entry point. Determine whether the library can make this call compile with -Yexplicit-nulls, and verify the result by compiling the reported example.

Written by the indexing model from the issue text.

Assessment

Tech stack
scala
Domain
developer-experience
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
30/100

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