function popRenderCallback()
{
if (count($this->_renderCallbacks) == 0) {
return Text_Wiki::error('Render callback popped when no render callbacks in stack');
} else {
$callback = array_pop($this->_renderCallbacks);
$this->_block = call_user_func($callback, $this->_block);
if (count($this->_blocks)) {
$parentBlock = array_pop($this->_blocks);
$this->_block = $parentBlock . $this->_block;
}
if (count($this->_renderCallbacks) == 0) {
$this->output .= $this->_block;
$this->_block = '';
}
}
}