Golang : Sort and reverse sort a slice of runes

Problem :

How to sort and reverse sort a slice of runes ?

Solution :

Sorting runes depends on the integer value of the rune and it will be ordered according to the integer values . Here's an example of how to sort slice of runes :

 package main

 import (
  "fmt"
  "sort"
 )

 type RuneSlice []rune

 func (p RuneSlice) Len() int { return len(p) }
 func (p RuneSlice) Less(i, j int) bool { return p[i] < p[j] }
 func (p RuneSlice) Swap(i, j int) { p[i], p[j] = p[j], p[i] }

 var runes RuneSlice = []rune{'可', '愛'} // sort based on the integer values of the runes

 func main() {
  // Runes
  fmt.Println("Original : ", runes[:])
  fmt.Println("Original : ", string(runes[:]))

  sort.Sort(RuneSlice(runes))

  fmt.Println("Sort : ", runes[:])
  fmt.Println("Sort : ", string(runes[:]))

  sort.Sort(sort.Reverse(runes[:]))

  fmt.Println("Reverse : ", runes[:])
  fmt.Println("Reverse : ", string(runes[:]))

 }

Output :

Original : [21487 24859]

Original : 可愛

Sort : [21487 24859]

Sort : 可愛

Reverse : [24859 21487]

Reverse : 愛可

UPDATE : You can import "github.com/cznic/sortutil" and use the RuneSlice.Sort() method ( see http://godoc.org/github.com/cznic/sortutil#RuneSlice ) as well if you prefer.