check whether a value class parameter is call-by-name

[Jasper-M]

fixes #5121

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[nicolasstucki]

We should reuse VarValParametersMayNotBeCallByName instead and maybe addapt a bit it's explanation.

[Jasper-M]

That was my first idea, but I thought it might be confusing, because it's not really a val and doesn't seem to behave like a case class parameter, which implicitly is a val, either.

[nicolasstucki]

You are right

[allanrenucci]

@nicolasstucki I don't think we should forbid this. dotc does not require value class parameter to be a val as opposed to scalac, so we don't need to impose this restriction.

We should fix the infinite loop of course

My concern was wrong

[nicolasstucki]

@Jasper-M then could you just change the commit message to be Fix #5121: Check if value class parameter is call-by-name. The fix looks good.

[nicolasstucki]

Thanks @Jasper-M

[Blaisorblade]

Thanks @Jasper-M, and nice to see you here!