60 lines
934 B
Go
60 lines
934 B
Go
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package main
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import (
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"fmt"
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)
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type EnvExample struct {
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Element
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}
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func (e EnvExample) Print(visitor IVisitor) {
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e.Element.Accept(visitor)
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}
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func GetEnv() string {
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return "testing"
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}
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// 定义访问者接口
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type IVisitor interface {
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Visit() // 访问者的访问方法
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}
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type ProductionVisitor struct {
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}
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func (v ProductionVisitor) Visit() {
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fmt.Println("这是生产环境")
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}
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type TestingVisitor struct {
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}
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func (t TestingVisitor) Visit() {
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fmt.Println("这是测试环境")
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}
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// 定义元素接口
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type IElement interface {
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Accept(visitor IVisitor)
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}
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type Element struct {
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}
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func (el Element) Accept(visitor IVisitor) {
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visitor.Visit()
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}
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func main() {
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// 创建一个元素
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e := new(Element)
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e.Accept(new(ProductionVisitor)) // output: 这是生产环境
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e.Accept(new(TestingVisitor)) // output: 这是测试环境
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m := new(EnvExample)
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m.Print(new(ProductionVisitor))
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m.Print(new(TestingVisitor))
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}
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