LIBXML_NOBLANKS到底是做什么的？

问：

两者之间有什么区别

$domd=new DOMDocument();
$domd->loadHTML($html, LIBXML_NOBLANKS);

和

$domd=new DOMDocument();
$domd->loadHTML($html, 0);

?

编辑：以防万一有人想删除所有空+空格文本节点（这并不完全是LIBXML_NOBLANKS所做的），这里有一个函数可以做到这一点，

$removeAnnoyingWhitespaceTextNodes = function (\DOMNode $node) use (&$removeAnnoyingWhitespaceTextNodes): void {
    if ($node->hasChildNodes()) {
        // Warning: it's important to do it backwards; if you do it forwards, the index for DOMNodeList might become invalidated;
        // that's why i don't use foreach() - don't change it (unless you know what you're doing, ofc)
        for ($i = $node->childNodes->length - 1; $i >= 0; --$i) {
            $removeAnnoyingWhitespaceTextNodes($node->childNodes->item($i));
        }
    }
    if ($node->nodeType === XML_TEXT_NODE && !$node->hasChildNodes() && !$node->hasAttributes() && (strlen(trim($node->textContent)) === 0)) {
        //echo "Removing annoying POS";
        // var_dump($node);
        $node->parentNode->removeChild($node);
    } //elseif ($node instanceof DOMText) { echo "not removed"; var_dump($node, $node->hasChildNodes(), $node->hasAttributes(), trim($node->textContent)); }
};
$dom=new DOMDocument();
$dom->loadHTML($html);
$removeAnnoyingWhitespaceTextNodes($dom);