Tour of Go 2.0

Pointers

Pointers hold memory addresses. Instead of copying a value, you point to where it lives.

The type *T is a pointer to a T value. Its zero value is nil.

var p *int

Use & to get a pointer to a variable:

i := 42
p = &i

Use * to read or write through that pointer — this is called dereferencing:

fmt.Println(*p) // read i through the pointer p
*p = 21         // set i through the pointer p

One thing Go doesn’t have: pointer arithmetic. No p++ tricks like in C.

main.go ▶ Run in Playground 
package main

import "fmt"

func main() {
	i, j := 42, 2701

	p := &i         // point to i
	fmt.Println(*p) // read i through the pointer
	*p = 21         // set i through the pointer
	fmt.Println(i)  // see the new value of i

	p = &j         // point to j
	*p = *p / 37   // divide j through the pointer
	fmt.Println(j) // see the new value of j
}