How to do it...

1. Open the console and create the folder chapter02/recipe09.
2. Navigate to the directory.
3. Create the case.go file with the following content:

        package main

        import (
          "fmt"
          "strings"
          "unicode"
        )

        const email = "ExamPle@domain.com"
        const name = "isaac newton"
        const upc = "upc"
        const i = "i"

        const snakeCase = "first_name"

        func main() {

          // For comparing the user input
          // sometimes it is better to
          // compare the input in a same
          // case.
          input := "Example@domain.com"
          input = strings.ToLower(input)
          emailToCompare := strings.ToLower(email)
          matches := input == emailToCompare
          fmt.Printf("Email matches: %t\n", matches)

          upcCode := strings.ToUpper(upc)
          fmt.Println("UPPER case: " + upcCode)
 
          // This digraph has different upper case and
          // title case.
          str := "dz"
          fmt.Printf("%s in upper: %s and title: %s \n", str,
                     strings.ToUpper(str), strings.ToTitle(str))

          // Use of XXXSpecial function
          title := strings.ToTitle(i)
          titleTurk := strings.ToTitleSpecial(unicode.TurkishCase, i)
          if title != titleTurk {
            fmt.Printf("ToTitle is defferent: %#U vs. %#U \n",
                       title[0], []rune(titleTurk)[0])
          }

          // In some cases the input
          // needs to be corrected in case.
          correctNameCase := strings.Title(name)
          fmt.Println("Corrected name: " + correctNameCase)

          // Converting the snake case
          // to camel case with use of
          // Title and ToLower functions.
          firstNameCamel := toCamelCase(snakeCase)
          fmt.Println("Camel case: " + firstNameCamel)

        }

        func toCamelCase(input string) string {
          titleSpace := strings.Title(strings.Replace(input, "_", " ", -1))
          camel := strings.Replace(titleSpace, " ", "", -1)
          return strings.ToLower(camel[:1]) + camel[1:]
        }

1. Run the code by executing go run case.go.
2. See the output in the Terminal: