Controlling case

There are a lot of practical tasks where the modification of case is the most common approach. Let's pick a few of these:

• Case-insensitive comparison
• Beginning the sentence with an automatic first capital 
• Camel-case to snake-case conversion

For these purposes, the strings package offers functions ToLower, ToUpper, ToTitle, and Title. 

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 = "[email protected]"
        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 := "[email protected]"
          input = strings...