Proxy pattern

main.go

package main

import "fmt"

type Driven interface {
    Drive()
}

type Car struct{}

func (c *Car) Drive() {
    fmt.Println("Car being driven")
}

type Driver struct {
    Age int
}

type CarProxy struct {
    car Car
    driver *Driver 
}

func (cp *CarProxy) Drive() {
    if cp.driver.Age >= 16 {
        cp.car.Drive()
    } else {
        fmt.Println("Driver too young")
    }
}

func NewCarProxy(driver *Driver) *CarProxy {
    return &CarProxy{Car{}, driver}
}

func main() {
    car := NewCarProxy(&Driver{12})
    car.Drive()
}
// output: Driver too yound