What's the point of having Nullables if we're still forced to do glorified if(*.isNull) ... else ... checks? I'd much rather use Scala's Option type that has Map and GetOrElse already baked in.
Also, the tooling around Scala is starting to mature. The Kotlins and Ceylons of the world are way behind Scala in this regard as well.
Sorry, but Option is just not better. One advantage of using a union type is that if I have a List<String?>, I just have a List<String|Null> (which maps to a plain List<String> at the JVM level) not a whole list of wrapper objects in a List<Option<String>>.
And of course Ceylon has sufficient syntax sugar so that you can write things like:
print(nameOrNull else "Gavin);
> Also, the tooling around Scala is starting to mature. The Kotlins and Ceylons of the world are way behind Scala in this regard as well.
WDYM?! I strongly beg to differ. Have you seriously tried out Ceylon's IDE? Or are you just speculating?
He was probably just reading your own mailing list. Why speculate, if he can get the state of tooling right from the core developers? :-)
Sure, those languages could just ship with additional classes which did that, but the problem is that they wouldn't be able to use the syntax sugar which is built-in for the special case of nulls as well as other language constructs like Scala's for-comprehensions which work for all types of a certain shape, not a single, built-in special-cased item.
Also, Ceylon doesn't need Either, since that is just a workaround for not having union types.
Seriously, union and intersection types are _really_ fundamental notions in set/type theory, and having them as basic constructs of the language makes the language _much_ more expressive.
I seriously urge you to try it out. You'll love them, I guarantee it.
So I can have my own type standing in for the ? instead of Null?
String? // Option[String]
...
String? // Validation[String]