| // +build OMIT | |
| package main | |
| import "fmt" | |
| // Index returns the index of x in s, or -1 if not found. | |
| func Index[T comparable](s []T, x T) int { | |
| for i, v := range s { | |
| // v and x are type T, which has the comparable | |
| // constraint, so we can use == here. | |
| if v == x { | |
| return i | |
| } | |
| } | |
| return -1 | |
| } | |
| func main() { | |
| // Index works on a slice of ints | |
| si := []int{10, 20, 15, -10} | |
| fmt.Println(Index(si, 15)) | |
| // Index also works on a slice of strings | |
| ss := []string{"foo", "bar", "baz"} | |
| fmt.Println(Index(ss, "hello")) | |
| } |