Neos\Cache\Backend\ApcBackend::removeIdentifierFromAllTags PHP Method

    protected function removeIdentifierFromAllTags($entryIdentifier)
    {
        // Get tags for this identifier
        $tags = $this->findTagsByIdentifier($entryIdentifier);
        // Deassociate tags with this identifier
        foreach ($tags as $tag) {
            $identifiers = $this->findIdentifiersByTag($tag);
            // Formally array_search() below should never return false due to
            // the behavior of findTagsByIdentifier(). But if reverse index is
            // corrupted, we still can get 'false' from array_search(). This is
            // not a problem because we are removing this identifier from
            // anywhere.
            if (($key = array_search($entryIdentifier, $identifiers)) !== false) {
                unset($identifiers[$key]);
                if (count($identifiers)) {
                    apc_store($this->identifierPrefix . 'tag_' . $tag, $identifiers);
                } else {
                    apc_delete($this->identifierPrefix . 'tag_' . $tag);
                }
            }
        }
        // Clear reverse tag index for this identifier
        apc_delete($this->identifierPrefix . 'ident_' . $entryIdentifier);
    }