SLC: `Conversion[A, Option[A]]`

[wtetzner]

@mberndt

We could also go one step further: add given[A] => Conversion[A | Null, Option[A]] = Option(_) to the Option companion object. This would make interop a little easier, allowing you to use nullable references from Java/JS/native in places where Option is expected.

The reverse might be nice too, e.g. for passing an Option to a native Java method. Though gating this one on into is a bit less obvious, since using it for native Java methods means you can’t actually use into. Maybe it could be automatically applied to non-Scala methods, and require into when you have a Scala method?

given[A] => Conversion[Option[A], A | Null] = _.orNull

Combined with Make Null a subclass of AnyVal under -Yexplicit-nulls and Proposal: Fixing null.methodOfAny() under explicit-nulls dealing with null could be both safe and ergonomic.