Output is: Array ( [doo] => doobar ) Array ( [doo] => doobar )

gistfile1.php

<?php

class Map{
    private $contents = array();
    function get( $keyArr ){
        return $this->contents[ $this->hash( $keyArr ) ];
    }
    function put( $keyArr, $valArr ){
        $this->contents[ $this->hash( $keyArr ) ] = $valArr;
    }

    function hash( $arr ){
        return @spl_object_hash( $arr );
    }
}

$map = new Map();
$foo = array("foo"=>"foobar");
$doo = array("doo"=>"doobar");
$map->put( $foo, $doo );
print_r( $map->get( $foo ) );

$foo["foo2"] = "foobar2";

print_r( $map->get($foo) );