napi_env

napi_env 用于表示底层 Node-API 实现可用于持久化 VM 特定状态的上下文。此结构在调用时传递给原生函数，并且在进行 Node-API 调用时必须传回。具体来说，调用初始原生函数时传入的相同 napi_env 必须传递给任何后续的嵌套 Node-API 调用。出于一般重用的目的缓存 napi_env，以及在不同 Worker 线程上运行的同一插件的实例之间传递 napi_env 是不允许的。当卸载原生插件的实例时，napi_env 变得无效。此事件的通知通过给 napi_add_env_cleanup_hook 和 napi_set_instance_data 的回调传递。

¥napi_env is used to represent a context that the underlying Node-API implementation can use to persist VM-specific state. This structure is passed to native functions when they're invoked, and it must be passed back when making Node-API calls. Specifically, the same napi_env that was passed in when the initial native function was called must be passed to any subsequent nested Node-API calls. Caching the napi_env for the purpose of general reuse, and passing the napi_env between instances of the same addon running on different Worker threads is not allowed. The napi_env becomes invalid when an instance of a native addon is unloaded. Notification of this event is delivered through the callbacks given to napi_add_env_cleanup_hook and napi_set_instance_data.