構造体スライスを使って sort 実装

filter.go

package main

import (
	"fmt"
	"log"
	"sort"
	"strings"
)

type filter struct {
	Priority int64
	Selector string
}

type filters []filter

func (f filters) String() string {
	var s []string
	for i := 0; i < len(f); i++ {
		s = append(s, fmt.Sprintf("%d:%s", f[i].Priority, f[i].Selector))
	}
	return strings.Join(s, ",")
}

func (f filters) Len() int {
	return len(f)
}

func (f filters) Swap(i, j int) {
	f[i], f[j] = f[j], f[i]
}

func (f filters) Less(i, j int) bool {
	return f[i].Priority < f[j].Priority
}

func main() {
	fs := filters{
		{4, "s4"},
		{2, "s2"},
		{3, "s3"},
		{1, "s1"},
		{6, "s6"},
		{5, "s5"},
	}

	log.Print(fs.String())
	sort.Sort(fs)
	log.Print(fs.String())
}