pointers

a := 5
// Store the memory address of the variable
b := &a // 0xc0000140e8
// Read the variable at a specific memory address
c := *b // 5
// Set the variable at a specific memory address
*b = 10
fmt.Println(a)  // 10

// Explicit definition
var d = *int
d = &a      // 0xc0000140e8

// So what's the point?
// Unscoped functions can operate directly on a memory address
// No need for globals
// Consider...
func pzero(xPtr *int) {
    *xPtr = 0
}
func zero(x int) {
    x = 0
}
func main() {
    x := 5
    y := 5
    fmt.Println(x, y) // 5, 5
    pzero(&x)
    zero(y)
    fmt.Println(x, y) // 0, 5
}