sortAndMaybeInsertString

sortAndMaybeInsertString.go

package sortAndMaybeInsertString

func sortAndMaybeInsertString(s string, a []string) []string {
	if len(a) == 0 {
		return append(a, s)
	}

	sort.Strings(a)

	i := sort.SearchStrings(a, s)

	if i < len(a) && a[i] == s {
		return a // return slice when string already present
	}

	// Without two copies and mandatory allocation, insert string into array at
	// index.
	a = append(a, a[len(a)-1])
	copy(a[i+1:], a[i:len(a)-1])
	a[i] = s

	return a
}