radixsort

General purpose Radix sort in go.

General purpose means that you can sort anything, not just int arrays.

You're supposed to use it like this:

type cell struct {
	rowKey, colKey uint
}

func (s []cell) SortKey(pos, priority int) (key int, ok bool) {
	switch priority {
		case 0:
			return s[pos].rowKey, true
		case 1:
			return s[pos].colKey, true
		default:
			return 0, false
	}
}

func (s []cell) Len() { return len(s) }
func (s []cell) Swap(i, j int) { s[i, j] = s[j, i] }

var cells []cell
cells = ...

radix.Sort(cells)

This should outperform the standard sort package, and does in my benchmarks.
Alas, it isn't quite done.