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0 pointsArcsech5y ago0 comments

> The lambda notation in C++ is really a thing Java could easily have.

Java has had lambda expressions, with what I would describe as cleaner syntax than C++'s, since JDK 8. Is there something I'm missing that C++'s have over Java's?

This has also lead to a lot of Java becoming much more functional, see especially the Stream API[0] (also added in JDK 8). I would say it's much, much easier to write functional-style code in Java than it is in Go.

[0]: https://docs.oracle.com/javase/8/docs/api/java/util/stream/S...

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4 comments · 2 top-level

vbezhenar5y ago· 2 in thread

Stream API is bad example of design IMO. Checked exceptions are not integrated (even if I don't like them, they're part of the language and are not going anywhere soon it seems). Simple operations require lots of ceremony (list.map(x -> x + 1) vs list.stream().map(x -> x + 1).collect(Collectors.toList())). Also Java lambdas can't change outer variables, so one have to resort to old tricks with one-item arrays.

Java lambdas are just syntax sugar for anonymous class from language point of view. They're implemented differently under the hood, but they don't bring anything new to developer, they just save few lines of code which is nice, but could be much better.

kelnos5y ago

> Also Java lambdas can't change outer variables, so one have to resort to old tricks with one-item arrays.

On the rare occasion that I need to do this, I usually find that I'm thinking about the problem the wrong way and there's a much clearer way to write it than messing with mutable variables outside my closures.

fomine35y ago

Tend to so but it depends on situation.

nobleach5y ago

Even though there is a book on Functional Programming in Go, I'd say, the entire idea really bends the language into an odd shape. Certainly one could implement map/reduce/filter (I think Rob Pike actually did create examples on his GitHub at one point), but the idiomatic paradigm of Go isn't FP. It's definitely not hard to beat in that arena! Now Kotlin or Scala on the other hand....

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