Comment by stickfigure
2 hours ago
> More generally than just Java, nullability is often a property not of a type but of a variable
I'm going to hard disagree here. And the syntax proposed in the Null-Restricted Value Class Types JEP is a major step backwards.
I want to banish nulls from my codebase, completely. I can currently do this with a variety of annotations (at the package-info.java level) and tooling, though it's not integrated well with the language.
Forcing exclamation marks into every variable and parameter is a lot of annoying noise that quite simply nobody will do. The default should be non-nullable, especially for value types.
Declaring whole types as non-nullable is less noisy and errorprone than annotating every variable declaration. If you aren't going to give me "declare the whole codebase as non-nullable" then at least give me something coarse-grained.
> the syntax proposed in the Null-Restricted Value Class Types JEP is a major step backwards. Forcing exclamation marks into every variable and parameter is a lot of annoying noise that quite simply nobody will do. The default should be non-nullable, especially for value types.
Then you didn't read the JEP draft (it's not an accepted JEP) carefully. It says, under "future work":
Providing a mechanism in the language to assert that all types in a certain context are implicitly null-restricted, without requiring the programmer to use explicit ! symbols.
In other words, the draft already incorporates your point, but JEPs (both drafts and actual JEPs) follow the pattern we've found to work so well, that features are best delivered piecemeal rather than in a big bang.
Having said that, I don't know the current plans for this matter, as that document is only in Draft status, so saying it's good or bad is pointless, as it's not even a proposal yet, just something being explored.
It's a proposal for a proposal, fine. Consider this my proposed feedback.
I don't think this syntax is desirable as currently proposed, and that one line under "future work" is doing far too much lifting. My sincere hope is that there are people closer to the process that also feel this way, they will provide similar feedback, and the next draft will be something completely different.