public static <A,B> Iterable<B> convert(final Iterable<A> entities,final F1<A,B> f) {
		return new Iterable<B>() {
			public Iterator<B> iterator() {
				final Iterator<A> it = entities.iterator();
				return new Iterator<B>() {
					public void remove() {
						it.remove();
					}
					public B next() {
						return f.e(it.next());
					}
					public boolean hasNext() {
						return it.hasNext();
					}
				};
			}
		};
	}