Easy way to get the keys in a map in alphabetical order

Question

In Go, what's the easiest way to get the keys in a map sorted alphabetically? This is the shortest way I can do it:

package main  import "container/vector" import "fmt" import "sort"  func main() {     m := map[string]string {"b":"15", "z":"123123", "x":"sdf", "a":"12"}     var keys vector.StringVector;     for k,_ := range ( m ) {             keys.Push(k)     }     sort.Sort( &keys )     fmt.Printf("%v\n", keys) } 

Answer 1

You are sorting an array of strings using StringVector. To minimize overhead, you could sort an array of strings.

package main  import (     "fmt"     "sort" )  func main() {     m := map[string]string{"b": "15", "z": "123123", "x": "sdf", "a": "12"}     mk := make([]string, len(m))     i := 0     for k, _ := range m {         mk[i] = k         i++     }     sort.Strings(mk)     fmt.Println(mk) } 

Output:

[a b x z] 

Answer 2

That would be most elegant method:

package main  import (     "fmt"     "sort" )  func main() {     m := map[string]string{"b": "15", "z": "123123", "x": "sdf", "a": "12"}     keys := make([]string, 0, len(m))     for key := range m {         keys = append(keys, key)     }     sort.Strings(keys)     fmt.Println(keys) }