// Copyright © 2018 Inanc Gumus // Learn Go Programming Course // License: https://creativecommons.org/licenses/by-nc-sa/4.0/ // // For more tutorials : https://learngoprogramming.com // In-person training : https://www.linkedin.com/in/inancgumus/ // Follow me on twitter: https://twitter.com/inancgumus package main import ( "fmt" "os" "strings" ) const usage = `[command] [string] Available commands: lower, upper and title` func main() { args := os.Args if len(args) != 3 { fmt.Println(usage) return } cmd, str := args[1], args[2] switch cmd { case "lower": fmt.Println(strings.ToLower(str)) case "upper": fmt.Println(strings.ToUpper(str)) case "title": fmt.Println(strings.Title(str)) default: fmt.Printf("Unknown command: %q\n", cmd) } }