Discussion on: Attempting to Learn Go - Listing Files By Extension

[Dirk Olbrich]

You don't mind?

func plainlist(m map[string][]string, order string) string {
    // 1. get all keys of the map
    var keys []string
    for k := range m {
        keys = append(keys, k)
    }

    // 2. sort by order type
    switch order {
    case "desc", "Desc", "DESC":
        for ext := range m {
            sort.Sort(sort.Reverse(sort.StringSlice(m[ext])))
        }
        sort.Sort(sort.Reverse(sort.StringSlice(keys)))
    default:
        for ext := range m {
            sort.Strings(m[ext])
        }
        sort.Strings(keys)
    }

    // 3. build a concatenated string
    var list string
    for _, k := range keys {
        list = fmt.Sprintf("%v\n%v", list, m[k])
    }
    return list
}

use it with:

fmt.Println(plainlist(m, "asc"))
fmt.Println(plainlist(m, "desc"))