PHP Manual: Creates a new instance

public Ds\Stack::__construct(mixed $values = ?)

Creates a new instance, using either a traversable object or an array for the initial values.

Example #1 Ds\Stack::__construct example

<?php
$stack = new \Ds\Stack();
print_r($stack);

$stack = new \Ds\Stack([1, 2, 3]);
print_r($stack);
?>

The above example will output something similar to:

Ds\Stack Object
(
)
Ds\Stack Object
(
    [0] => 3
    [1] => 2
    [2] => 1
)