ModuleHandler::verifyImplementations

protected ModuleHandler::verifyImplementations(&$implementations, $hook)

protected function verifyImplementations(&$implementations, $hook) {
  $all_valid = TRUE;
  foreach ($implementations as $module => $group) {
    // If this hook implementation is stored in a lazy-loaded file, include
    // that file first.
    if ($group) {
      $this->loadInclude($module, 'inc', "$module.$group");
    }
    // It is possible that a module removed a hook implementation without
    // the implementations cache being rebuilt yet, so we check whether the
    // function exists on each request to avoid undefined function errors.
    // Since ModuleHandler::implementsHook() may needlessly try to
    // load the include file again, function_exists() is used directly here.
    if (!function_exists($module . '_' . $hook)) {
      // Clear out the stale implementation from the cache and force a cache
      // refresh to forget about no longer existing hook implementations.
      unset($implementations[$module]);
      // One of the implementations did not exist and needs to be removed in
      // the cache.
      $all_valid = FALSE;
    }
  }
  return $all_valid;
}