Golang เรื่องที่อาจผิดพลาดกับ Array, Slice และ Map

arr := [3]int{0,1,2} 

sli := []int{0,1,2} 

m := map[string]bool{ "1": true, "2": true, "3": true, } 

before := []string{ "apple", "banana", "cherry", } fmt.Println("Before: ", before) /* Before: [apple banana cherry] */ after := before before[0] = "__imposter__" fmt.Println("After: ", after) /* After: [__imposter__ banana cherry] */ 

Before: [apple banana cherry] After: [__imposter__ banana cherry] 

before[0] = "__imposter__" fmt.Println("After: ", after) /* After: [__imposter__ banana cherry] */ 

package main import "fmt" func main() { before := []string{ "apple", "banana", "cherry", } fmt.Println("before: ", before) /*before: [apple banana cherry]*/ after := before UpdateSlice(before) fmt.Println("after: ", after) /*after: [__imposter__ banana cherry]*/ } func UpdateSlice(v []string) { if len(v) <= 0 { return } v[0] = "__imposter__" } 

copy(destination, source) 

before := []string{ "apple", "banana", "cherry", } fmt.Println("Before: ", before) /* Before: [apple banana cherry] */ after := make([]string, len(before)) copy(after, before) before[0] = "__imposter__" fmt.Println("After: ", after) /* After: [apple banana cherry] */ 

before := map[string]bool{ "apple": true, "banana": true, "cherry": true, } after := before before["apple"] = false for k, v := range after { fmt.Printf("%v:t %vn", k, v) } 

apple: false banana: true cherry: true 

maps.Clone(source) 

before := map[string]bool{ "apple": true, "banana": true, "cherry": true, } after := maps.Clone(before) before["apple"] = false for k, v := range after { fmt.Printf("%v:t %vn", k, v) } 

apple: true banana: true cherry: true