Enable explicit-nulls and unsafe nulls by default with null under AnyVal#26296
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HarrisL2 wants to merge 15 commits into
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Enable explicit-nulls and unsafe nulls by default with null under AnyVal#26296HarrisL2 wants to merge 15 commits into
HarrisL2 wants to merge 15 commits into
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That removes it from the top of the hierarchy, de-emphasizing its importance. It makes sense because it has all the properties of other `AnyVal`s: "two" instances of `Null` "re-created" from the keyword `null` are indistinguishible from each other. So it has structural equality. This does not change the erasure of any type, because `AnyVal` erases to `Object` anyway. Unfortunately, this requires complicating the loading mechanism for `scala.Null`. It now extends a class that can be compiled from source, and that is incompatible with it being a "core" class that is forced in `Definitions.init()`. We make it a synthesized class instead, like the magic `FunctionN` classes. I'm not happy about this. The silver lining is that, once we actually move all-in to explicit-nulls, we will be able to define `Null` itself in source, which will remove all of that magic. If you have trouble wrapping your head around `Null <:< AnyVal`, observe that `null: Null` and `(): Unit` have a lot in common. They are both types with a singleton instance, accessible with syntax. `null` is only `== null`, and `()` is only `== ()`. Moreover, they do not have the `eq` operator.
…it-nulls-under-anyval
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Testing the effects of AnyVal null by enabling it by default.
How much have you relied on LLM-based tools in this contribution?
Not at all
How was the solution tested?
Covered by existing tests (this is a refactoring)