gistfile1.txt

#ruby
[1,2,3,4].select{ |x| x.even? }

#python
[x for x in [1,2,3,4] if not x%2]
#or, more norvingly
filter(lambda x: not x%2, [1,2,3,4])

#clojure
(filter #(even? % ) [1 2 3 4])

#scheme
(filter (lambda (x) (even? x)) '(1 2 3 4))

#common lisp
(remove-if-not (lambda (x) (evenp x)) '(1 2 3 4))

#javascript
[1,2,3,4].filter(function(x){return !(x%2)})

#java
import java.util.ArrayList;
import java.util.Arrays;
public class filter {
    public static void main (String [] args)
    {
        Integer [] a = {1,2,3,4};

        System.out.println(
                    new ArrayList<Integer>(Arrays.asList(a)){{
                        ArrayList<Integer> clon = (ArrayList<Integer>)this.clone();
                        for(Integer e : clon){
                            if(e.intValue()%2 != 0)
                                this.remove(e);
                        }
                    }}
                );
    }
}

Or, if you're using Google's Guava library (which everyone should, and is likely to be rolled into JDK8), it's just:

Iterables.filter(
    Lists.newArrayList(1, 2, 3, 4),
    new Predicate<Integer>() { public boolean apply(Integer x) { return x % 2 == 0; } });

(Plus all the surrounding main stuff which it's no longer cool to criticize Java for requiring, as it's just not that big a deal).

You should comment here: https://gist.github.com/817504

ruby

require 'activesupport'
[1,2,3,4].select &:even?