PHP数组重复值

Question

在我的自定义Moodle plugin中，我为每个日期获取车库，他们已预订，所以我应该有一个这样的列表：

Date1 - Garage 1
Date2 - Garage 2
Date3 - Garage 2

如您所见，一个车库可以在不同的日期重复。

我用这段代码得到车库名称：

$garagenames = array();
foreach ($garage as $rawgarage) {
        $venue = array();
        if (!empty($rawgarage->building)) {
            $venue[] = $rawgarage->building;
        }
        if (!empty($rawgarage->address)) {
            $venue[] = $rawgarage->address;
        }
        $garagename = implode(', ', $venue);

    $garagenames[] = $garagename;
}

function _remove_empty_internal($value) {
  return strlen($value)>1;
}

function remove_empty($array) {
  return array_filter($array, '_remove_empty_internal');
}

$dates_arr_clean = remove_empty($allsessiondates);
$rooms_arr_clean = remove_empty($garagenames);
$rooms_arr = array();//explode("/n", $garages);

$datesgarages = "";

foreach ($dates_arr_clean as $date) {
    if($garages_arr_clean)
        $datesgarages .= $date . " - " . array_shift($garages_arr_clean) . "<br />";
    else
        $datesgarages .= $date . "<br />";
}

$rawgarage的var_dump是：

(stdClass)#65 (10) { ["id"]=> string(1) "2" ["name"]=> string(8) "Garage1" ["building"]=> string(18) "HQ" ["address"]=> string(14) "1 Times Square" ["capacity"]=> string(2) "1" ["type"]=> string(8) "internal" ["description"]=> string(0) "" ["custom"]=> string(1) "0" ["timecreated"]=> string(10) "1458557926" ["timemodified"]=> string(10) "1459842497" }

问题是重复值没有显示，所以我们变成：

    Date1 - Garage 1
    Date2 - Garage 2
    Date3 - **missing** (Garage 2)

我在代码中缺少什么才能显示重复值？