Wordpress - Get the post terms

functions.php

<?php

/**
 * Get the terms of post
 * @param  object $p         The post
 * @param  string $class     CSS Class
 * @param  string $separator
 * @return string            The terms
 */
function get_post_terms($p, $class = 'post-preview__cat', $separator = '') {
  $links = array();
  $p->cats = wp_get_post_categories($p->ID);

  foreach ($p->cats as $c) {
    $cat = get_category($c);

    $links[] = "<a href=\"" . get_category_link($cat->term_id) . "\" class=\"$class\">" . $cat->name . "</a>";
  }

  return implode($separator, $links);
}