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by youerbt 2444 days ago
Java is also advertised as "enterprise" language and it can't even encode in its type system that a piece of data can be missing. Or maybe it can, with Optional<T>, thanks Haskell.

I can't tell I had less problems understanding magic container IoC stuff than most Haskell concepts.
2 comments
tsimionescu 2443 days ago
To be pedantic, Java perfectly encodes the information that a piece of data can be missing - any type supports null as a valid value. What it can't do is encode the information that a piece of data CAN'T be missing.
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bspammer 2443 days ago
To be even more pedantic, Java's primitive types (int instead of Integer etc.) have this feature. They can't be null.
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the_af 2443 days ago
> maybe it can, with Optional<T>

Not even that. Java's optionals are almost useless, needlessly verbose, you still don't have pattern matching, and there's also still null to contend with.

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