regexpswitch.go

package main

import "fmt"
import "regexp"

var email = regexp.MustCompile(`^[^@]+@[^@.]+\.[^@.]+$`)
var shortPhone = regexp.MustCompile(`^[0-9][0-9][0-9][.\-]?[0-9][0-9][0-9][0-9]$`)
var longPhone = regexp.MustCompile(`^[(]?[0-9][0-9][0-9][). \-]*[0-9][0-9][0-9][.\-]?[0-9][0-9][0-9][0-9]$`)

func main() {
  contacts := []string{
    "(111) 555-4444",
    "foo@example.com",
    "555-1234",
    "123.555.4567",
    "1 infinite loop",
  }
  for _, contact := range contacts {
    switch {
    case email.MatchString(contact):
      fmt.Println(contact, "is an email")
    case shortPhone.MatchString(contact):
      fmt.Println(contact, "is a short phone number")
    case longPhone.MatchString(contact):
      fmt.Println(contact, "is a long phone number")
    default:
      fmt.Println(contact, "is not recognized")
    }
  }
}