Hacker News Reader

Comment by mruts | Hacker News Reader

If Java were to support to scale/fp-like match statements with case objects and unapply methods, it would probably be good enough to obviate Scala (It would still be distinctly worse though).

Pattern matching is such a powerful feature. I wish more languages (like python) would realize it’s value and add it.

View on HN

Hopefully project Amber will arrive soon.

https://cr.openjdk.java.net/~briangoetz/amber/pattern-match....

I suspect trying to combine pattern matching with java’s container classes would be an exercise in frustration. What struck me about scala was how much nicer its standard library is, even when using only things java has equivalents for.

Is it?

I've used Scala before.

There are some cases, like compilers where I could see matching and extracting complex and nested patterns to be useful.

But in most cases monadic operations/functors plus if/else seems pretty much as good.

Unfortunately monads aren’t in base scala (as an explicit class at least), so often you need to do some ad-hoc pattern matching on tuples or data structures and pattern matching really helps in de-structuring and binding relevant variables.

I probably use monadic operations (map, fold, etc) at least 5-10 times a day in my job (I’m a scala dev), and match expressions at least 3-5 times a day.

So pretty useful I’d say. Though then again I’m dealing with some pretty baroque case classes that contain dozens of values of financial information.

> Unfortunately monads aren’t in base scala (as an explicit class at least)

Scalaz and cats are perhaps the most common dependencies in the Scala ecosystem.

This is on the roadmap.

Reply on news.ycombinator.com