Ds\Stack::peek

(PECL ds >= 1.0.0)

Ds\Stack::peekReturns the value at the top of the stack

说明

public Ds\Stack::peek ( ) : mixed

Returns the value at the top of the stack, but does not remove it.

参数

此函数没有参数。

返回值

The value at the top of the stack.

错误/异常

UnderflowException if empty.

范例

Example #1 Ds\Stack::peek() example

<?php
$stack 
= new \Ds\Stack();

$stack->push("a");
$stack->push("b");
$stack->push("c");

var_dump($stack->peek());
?>

以上例程的输出类似于:

string(1) "c"

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