简单的条件语句不起作用（等于）wordpress

Question

我有一个简单的条件语句来检查woocommerce / wordpress中的某个产品父类别，但即使值为真（对我来说）它也不起作用。有什么想法吗？

function get_parent_terms($term) {
    if ($term->parent > 0) {
        $term = get_term_by("id", $term->parent, "product_cat");
        if ($term->parent > 0) {
            get_parent_terms($term);
        } else return $term;
    }
    else return $term;
}

# Will return all categories of a product, including parent categories
function all_cat_classes($post) {
    $cats = ""; 
    $terms = get_the_terms($post->ID, "product_cat");
    $key = 0;

    // foreach product_cat get main top product_cat
    foreach ($terms as $cat) {
        $cat = get_parent_terms($cat);
        $cats .= (strpos($cats, $cat->slug) === false ? $cat->slug." " : "");
        $key++;
    }

    return $cats;
}

然后此代码最终为false并回显nope: causes

$damaincat = all_cat_classes($post);
if($damaincat == 'causes')  echo '<style>#text-3 { display: none !important; }</style>'; else echo 'nope: '.$damaincat; 

我被绊倒= 0（