I want generics!

interfaces.go

package main

import "fmt"

type Account struct {
	Name    string
	balance int64
}

func (a *Account) Balance() int64 {
	return a.balance
}

type USDAccount struct {
	name        string
	balance     int64
	stateOrigin string
}

func (a *USDAccount) Name() string {
	return a.name
}

func (a *USDAccount) Balance() int64 {
	return a.balance
}

type CADAccount struct {
	name           string
	balance        int64
	provinceOrigin string
}

func (a *CADAccount) Name() string {
	return a.name
}

func (a *CADAccount) Balance() int64 {
	return a.balance
}

type WithBalance interface {
	Name() string
	Balance() int64
}

func PrintAccounts(accounts []WithBalance) {
	for _, acc := range accounts {
		fmt.Printf("%s = %d\n", acc.Name(), acc.Balance())
	}
}

func main() {
	us_accounts := []*USDAccount{}
	us_accounts = append(us_accounts, &USDAccount{name: "USA account 1", balance: 0})
	us_accounts = append(us_accounts, &USDAccount{name: "USA account 2", balance: 0})

	cad_accounts := []*CADAccount{}
	cad_accounts = append(cad_accounts, &CADAccount{name: "CAD account 1", balance: 0})
	cad_accounts = append(cad_accounts, &CADAccount{name: "CAD account 2", balance: 0})

	PrintAccounts(us_accounts)
	PrintAccounts(cad_accounts)
}