How to do it...

1. Open the console and create the folder chapter02/recipe02.
2. Navigate to the directory.
3. Create the whitespace.go file with the following content:

        package main

        import (
          "fmt"
          "strings"
        )

        const refString = "Mary had a little lamb"
 
        func main() {

          words := strings.Fields(refString)
          for idx, word := range words {
            fmt.Printf("Word %d is: %s\n", idx, word)
          }

        }

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

1. Create another file called anyother.go with the following content:

        package main

        import (
          "fmt"
          "strings"
        )

        const refString = "Mary_had a little_lamb"

        func main() {

          words := strings.Split(refString, "_")
          for idx, word := range words {
            fmt.Printf("Word %d is: %s\n", idx, word)
          }

        }

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

1. Create another file called specfunction.go with the following content:

        package main

        import (
          "fmt"
          "strings"
         )

         const refString = "Mary*had,a%little_lamb"

         func main() {

           // The splitFunc is called for each
           // rune in a string. If the rune
           // equals any of character in a "*%,_"
           // the refString is split.
           splitFunc := func(r rune) bool {
             return strings.ContainsRune("*%,_", r)
           }

           words := strings.FieldsFunc(refString, splitFunc)
           for idx, word := range words {
             fmt.Printf("Word %d is: %s\n", idx, word)
           }

        }

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

1. Create another file called regex.go with the following content:

        package main

        import (
          "fmt"
          "regexp"
        )

        const refString = "Mary*had,a%little_lamb"

        func main() {

          words := regexp.MustCompile("[*,%_]{1}").Split(refString, -1)
          for idx, word := range words {
            fmt.Printf("Word %d is: %s\n", idx, word)
          }

        }

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