(PECL ds >= 1.0.0)
Ds\Stack::peek — Returns the value at the top of the stack
Returns the value at the top of the stack, but does not remove it.
此函數沒(méi)有參數。
The value at the top of the stack.
UnderflowException if empty.
示例 #1 Ds\Stack::peek() example
<?php
$stack = new \Ds\Stack();
$stack->push("a");
$stack->push("b");
$stack->push("c");
var_dump($stack->peek());
?>
以上例程的輸出類(lèi)似于：
string(1) "c"