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From: Cthun <cthun_117@qmail.net.au>
Newsgroups: comp.lang.java.programmer
Subject: Re: Style Police (a rant)
Date: Sun, 11 Sep 2011 17:11:05 -0400
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On 11/09/2011 3:20 PM, Wanja Gayk wrote:
$ public<T>  List<T>  withoutDupes(final List<T>  xs) {
$   return new Object() {
$    <T>  List<T>  withoutDupes(final List<T>  head, final List<T>  tail) {
$     if(tail.isEmpty()){return head;}
$     if (head.contains(tail.get(0))) {
$      return withoutDupes(head, tail.subList(1, tail.size()));
$     }
$     return withoutDupes(
$        new ArrayList<T>(head){{add(tail.get(0));}}
$      , tail.subList(1, tail.size())
$     );
$    }
$   }.withoutDupes(Collections.<T>emptyList(), xs);
$ }

> This is a whole different beast (and prone to crash with a stack
> overflow exception on larger lists by the way).
> Admitted, it is not entirely functional due to the "add"-call, but quite
> close. Still it is pretty compact code (there is a certain beauty in
> recursion, isn't it?) and not hard to understand either.
>
> Bullying someone to functional code would be pretty stupid, as the
> current JVMs still have a hard time detecting tail recursions and it
> lacks data structures that do lazy evaluation in the Java SE.

There's a way around that, and it's called Clojure. It compiles to JVM 
bytecode and has both lazy lists and a special operator for doing tail 
recursion (the compiler turns it into an iteration).