Compare slices ignoring order of elements

slice_elements_match.go

// ElementsMatch compares two slices ignoring the order of the elements. If
// there are duplicate elements, the number of appearances of each of them in
// both lists should match. Empty and nil slices are treated as equal.
func ElementsMatch[S ~[]E, E comparable](s1, s2 S) bool {
	f len(s1) != len(s2) {
		return false
	}
	if len(s1) == 0 && len(s2) == 0 {
		return true
	}
	diff := make(map[E]int, len(s1))
	for i := range s1 {
		diff[s1[i]]++
	}
	for _, v2 := range s2 {
		if _, ok := diff[v2]; !ok {
			return false
		}
		diff[v2]--
		if diff[v2] == 0 {
			delete(diff, v2)
		}
	}
	return len(diff) == 0
}