Relevanssi filter to get exact title matches on top

relevanssi-exact-title-match.php

<?php

add_filter('relevanssi_hits_filter', 'rlv_find_exact_title_match');
function rlv_find_exact_title_match($hits) {
  $title_match = array();
  $the_rest = array();
  foreach ($hits[0] as $hit) {
    if (mb_strtolower($hit->post_title) == $hits[1]) {
      $title_match[] = $hit;
    }
    else {
      $the_rest[] = $hit;
    }
  }
  global $title_match_found;
  if (count($title_match) > 0) {
    $title_match_found = true;
    !empty($the_rest) ? $hits[0] = array_merge($title_match, $the_rest) : $hits[0] = $title_match;
  }
  else {
    $hits[0] = $the_rest;
  }
  return $hits;
}

?>