Example for pointer receiver.

exforprecv.go

package main

import (
	"fmt"
	"log"
)

// IntQueue is a FIFO queue.
type IntQueue struct {
	queue []int
}

// Push an element onto the queue.
func (q *IntQueue) Push(i int) {
	// mutation
	q.queue = append(q.queue, i)
}

// Pop from the queue.
func (q *IntQueue) Pop() int {
	if len(q.queue) < 1 {
		log.Fatal("pop from an empty queue")
	}
	i := len(q.queue) - 1
	v := q.queue[i]
	// mutation
	q.queue = q.queue[:i]
	return v
}

func (q *IntQueue) Size() int {
	return len(q.queue)
}

func main() {
	q := &IntQueue{}
	q.Push(100)
	q.Push(200)
	fmt.Println(q)
	q.Pop()
	fmt.Println(q)
	q.Pop()
	fmt.Println(q)
}