Go チャネルで後入れ先出し (LIFO) 動作を実装するにはどうすればよいですか?

<code class="go">import "container/heap"

type Stack []int

func (s Stack) Len() int           { return len(s) }
func (s Stack) Less(i, j int) bool { return s[i] > s[j] }    // Reverse the comparison for LIFO

// Initialize the stack
var stack Stack

// Push an element onto the stack
func Push(x int) { heap.Push(&stack, x) }

// Pop an element from the stack
func Pop() int {
    old := stack
    l := len(old)
    x := old[l-1]
    old = old[:l-1]
    heap.Init(&stack)
    for i := range old {
        heap.Push(&stack, old[i])
    }
    return x
}</code>