Quick sort using generics in Rust

quicksort.rs

// quicksort.rs

use cmp::Ord;

fn partition<T: Ord>(ns: &mut [T], l: uint, r: uint) -> uint {
  let p = &mut ns[l];
  let mut i = l + 1;
  for uint::range(l+1,r) |j| {
    if ns[j] < *p {
      ns[i] <-> ns[j];
      i += 1;
    }
  }
  ns[l] <-> ns[i-1];
  i - 1
}

fn quicksort<T: Ord>(ns: &mut [T], l: uint, r: uint) -> uint {
  if r-l <= 1{
    0
  }else{
    let p = partition(ns,l,r);
    let a = quicksort(ns,l,p);
    let b = quicksort(ns,p+1,r);
    a + b + (r-l-1)
  }
}

fn main(){
  let nums: ~mut [int] = vec::to_mut(~[1,3,2,5,10,4,6,7,8,9]);
  print_vector(nums);
  io::println("");
  quicksort(nums,0,vec::len(nums));
  print_vector(nums);
}

fn print_vector(ns: &[int]) {
  for ns.each |&n| {
    io::print(fmt!("%d ",n));
  }
  io::println("");
}