package smtpserver import ( "fmt" "strings" ) const TLD = ".yggmail" func parseAddress(email string) (string, string, error) { if !strings.HasSuffix(email, TLD) { return "", "", fmt.Errorf("invalid TLD") } at := strings.LastIndex(email, "@") if at == 0 { return "", "", fmt.Errorf("invalid email address") } return email[:at], strings.TrimSuffix(email[at+1:], TLD), nil }