文档的本部分似乎不正确.据我所知，zlib扩展名始终*默认为启用.

This section of the documentation appears to be incorrect. As far as I can tell, the zlib extension has always* been enabled by default.

虽然某些系统上可能未加载此扩展名，但这种情况极为罕见.您无需为缺少它而添加解决方法-只需将其声明为要求并继续即可.

While it's possible that this extension is not loaded on some systems, this is extremely rare. You do not need to add workarounds for its absence — just state it as a requirement and move on.

*:也就是说，至少回到 PHP 4.0.

*: That is, back to at least PHP 4.0.