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",
		"[email protected]",
		"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")
		}
	}
}