[dustingetz]

here is some code i wrote last week: https://gist.github.com/3758511

it was a method i extracted from some old code somewhere else while i fixed a bug in it. the functional programmer in me sees opportunities to generalize (and prevent future bugs here), so i try to refactor it into a defaultdict and a higher order function, using guava. 20 minutes later I still don't have working code, i revert, curse the gods because this is a 30 second refactor even in python let alone clojure, and move on, i don't have time for this shit.

its not about it looking different. it doesn't matter that closures and objects are turing equivalent. its a syntax problem.writing functional java code has too much friction and is not worth it.

this is not even getting into how any hardcore functional code needs persistent data structures to be fast, which means a) you need to write your code against a 3rd party collections library instead of JDK provided implementations, and b) any interop with 3rd party code will now imply a conversion (copy) at the boundary.

[anakanemison]

I agree that Java can be awkward if you're trying to write using functional idioms.

Still, in case you were interested, I commented on your gist with a potential solution.