static L<Byte> intListToByteList_littleEndian(L<Int> l) {
  if (l == null) null;
  int n = l(l)*4;
  
  ret new RandomAccessAbstractList<Byte>() {
    public int size() { ret n; }
    
    public Byte get(int i) {
      ret byteFromInt_littleEndian(l.get(i/4), i & 3);
    }
    
    public Byte set(int i, Byte val) {
      int old = l.get(i/4);
      int newInt = replaceByteInInt_littleEndian(old, i & 3, val);
      if (old != newInt)
        l.set(i/4, newInt);
      ret byteFromInt_littleEndian(old, i & 3);
    }
  };
}

Began life as a copy of #1033086