Golang策略模式如何实现算法解耦

type DiscountStrategy interface {
    Calculate(price float64) float64
}

type NormalUserDiscount struct{}
func (d NormalUserDiscount) Calculate(price float64) float64 {
return price  0.95 // 95折
}
type VIPUserDiscount struct{}
func (d VIPUserDiscount) Calculate(price float64) float64 {
return price  0.9 // 9折
}
type SuperUserDiscount struct{}
func (d SuperUserDiscount) Calculate(price float64) float64 {
return price  0.8 // 8折
}

type PriceCalculator struct {
    strategy DiscountStrategy
}
func (c *PriceCalculator) SetStrategy(s DiscountStrategy) {
c.strategy = s
}
func (c *PriceCalculator) GetFinalPrice(price float64) float64 {
if c.strategy == nil {
panic("strategy not set")
}
return c.strategy.Calculate(price)
}

calculator := &PriceCalculator{}
var strategy DiscountStrategy
switch userType {
case "normal":
strategy = &NormalUserDiscount{}
case "vip":
strategy = &VIPUserDiscount{}
case "super":
strategy = &SuperUserDiscount{}
}
calculator.SetStrategy(strategy)
finalPrice := calculator.GetFinalPrice(100)