GoのSliceの重複をMapを使って削除する ref: https://qiita.com/Sekky0905/items/ba2215981693b36e9982

file0.go

package main

import "fmt"

func main() {
    list := []string{"Go", "Java", "Python", "Go", "Ruby", "Go"}

    m := make(map[string]struct{})

    newList := make([]string, 0)

    for _, element := range list {
        // mapでは、第二引数にその値が入っているかどうかの真偽値が入っている
        if _, ok := m[element]; !ok {
            m[element] = struct{}{}
            newList = append(newList, element)
        }
    }

    fmt.Printf("mapの中身 %#v\n", m)
    fmt.Printf("重複削除後 %#v\n", newList)
}

file1.txt

mapの中身 map[string]struct {}{"Go":struct {}{}, "Java":struct {}{}, "Python":struct {}{}, "Ruby":struct {}{}}
重複削除後 []string{"Go", "Java", "Python", "Ruby"}