bkv

If you don't think it's an important distinction then your real beef is that the developer can choose to panic in certain scenarios, which of course is silly when put in context.

>Except these aren't at all the same. With a reference, you have no good way of telling whether your reference IS nullable.

As the article mentions, we have annotations to do just that.

>Therefore it is trivial to a) train developer habits to always check before fetch, and b) enforce an isPresent check with static checks.

Again, if we're using static analysis to verify the correct use of Optional, why are we using optional at all? Why wouldn't we use static checks to verify null references can't be dereferenced, instead of hypothetical yet-to-be-implemented static checks that may not be implemented anyway? See https://github.com/findbugsproject/findbugs/issues/56

That is the old bug tracker. An issue was submitted on the official tracker and immediately closed. See https://github.com/findbugsproject/findbugs/issues/56 for explanation.

>Actually, (much to my disappointment as I'm just learning rust) you can just take an Option or Result and .unwrap() and the compiler won't complain at you

unwrap() is a convenience method that still uses exhaustive pattern matching and will panic if no value is present. The developer is making a conscious decision to panic in a not-present scenario, and on a case-by-case basis. The compiler is still doing it's job. This is different than java, where a get() on a non-present value is a runtime violation.

>Yes, you can write get() and risk an exception. So don't do that.

Yes, you can dereference a null pointer and risk an exception. So don't do that.

See where this is going?

The problem with Java's optional is that it is by all appearances (in name and high-level description), a general purpose optional, albeit with a ton of gotchas that will result in people saying "Just don't do that."

Java's optional is not a general purpose option type. In fact, its intended use-case is very specific, according to a rather obscure SO answer by Brian Goetz: http://stackoverflow.com/a/26328555/547365

This is, of course, just tribal knowledge, meaning people are going to be doing shit with optional that they shouldn't, and it's going to be messy.