Adapter

package main

import "fmt"

type Charger interface {
    ChargePhone()
}

type OldCharger struct{}
func (o *OldCharger) PlugIn() {
    fmt.Println("Charging with old charger")
}

type ChargerAdapter struct {
    old *OldCharger
}

func (a *ChargerAdapter) ChargePhone() {
    a.old.PlugIn()
}

func main() {
    old := &OldCharger{}
    var charger Charger = &ChargerAdapter{old: old}

    charger.ChargePhone()
}