GoのSliceをSortする(sort.Sliceとsort.SliceStable) ref: https://qiita.com/Sekky0905/items/2d5ccd6d076106e9d21c

file0.go

func Slice(slice interface{}, less func(i, j int) bool)

file1.go

        people := []Person{
            {Name: "V", Age: 3},
            {Name: "K", Age: 3},
            {Name: "Y", Age: 3},
            {Name: "A", Age: 4},
            {Name: "E", Age: 3},
            {Name: "D", Age: 1},
            {Name: "C", Age: 3},
            {Name: "X", Age: 2},
            {Name: "B", Age: 3},
        }

        sort.Slice(people, func(i, j int) bool { return people[i].Name < people[j].Name })
        fmt.Printf("NameでSort(Not-Stable):%+v\n", people)

        sort.Slice(people, func(i, j int) bool { return people[i].Age < people[j].Age })
        fmt.Printf("AgeでSort(Not-Stable):%+v\n", people)

file2.txt

NameでSort(Not-Stable):[{Name:A Age:4} {Name:B Age:3} {Name:C Age:3} {Name:D Age:1} {Name:E Age:3} {Name:K Age:3} {Name:V Age:3} {Name:X Age:2} {Name:Y Age:3}]
AgeでSort(Not-Stable):[{Name:D Age:1} {Name:X Age:2} {Name:V Age:3} {Name:C Age:3} {Name:E Age:3} {Name:K Age:3} {Name:B Age:3} {Name:Y Age:3} {Name:A Age:4}]

file3.go

func SliceStable(slice interface{}, less func(i, j int) bool)

file4.go

people2 := []Person{
        {Name: "V", Age: 3},
        {Name: "K", Age: 3},
        {Name: "Y", Age: 3},
        {Name: "A", Age: 4},
        {Name: "E", Age: 3},
        {Name: "D", Age: 1},
        {Name: "C", Age: 3},
        {Name: "X", Age: 2},
        {Name: "B", Age: 3},
    }

    sort.SliceStable(people2, func(i, j int) bool { return people2[i].Name < people2[j].Name })
    fmt.Printf("NameでSort(Stable):%+v\n", people2)

    sort.SliceStable(people2, func(i, j int) bool { return people2[i].Age < people2[j].Age })
    fmt.Printf("AgeでSort:%+v\n", people2)
}

file5.txt

NameでSort(Stable):[{Name:A Age:4} {Name:B Age:3} {Name:C Age:3} {Name:D Age:1} {Name:E Age:3} {Name:K Age:3} {Name:V Age:3} {Name:X Age:2} {Name:Y Age:3}]
AgeでSort:[{Name:D Age:1} {Name:X Age:2} {Name:B Age:3} {Name:C Age:3} {Name:E Age:3} {Name:K Age:3} {Name:V Age:3} {Name:Y Age:3} {Name:A Age:4}]