写入指针，但是编译器仍然抱怨未使用的变量

Question

The following code causes a compilation error:

main.go:8:9: p declared and not used

package main

func main() {
    pointers := make([]*int, 5)

    a := 1 // create an int

    for _, p := range pointers {
        p = &a
    }
}

Writing to p doesn't count as using it?

Answer 1

P is only scoped to the loop block and essentially gets a copy of a pointers slice element every time it goes through the loop. This would work though:

package main

import "fmt"

func main() {
    pointers := make([]*int, 5)

    a := 1 // create an int

    for i := range pointers {
        pointers[i] = &a
    }
    fmt.Println(pointers)
}

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