flow like the river

BACK_BACK/node_modules/node-addon-api/doc/promises.md

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+# Promise
+
+The `Napi::Promise` class, along with its `Napi::Promise::Deferred` class, implement the ability to create, resolve, and reject Promise objects.
+
+The basic approach is to create a `Napi::Promise::Deferred` object and return to your caller the value returned by the `Napi::Promise::Deferred::Promise` method. For example:
+
+```cpp
+Napi::Value YourFunction(const Napi::CallbackInfo& info) {
+  // your code goes here...
+  Napi::Promise::Deferred deferred = Napi::Promise::Deferred::New(info.Env());
+  // deferred needs to survive this call...
+  return deferred.Promise();
+}
+```
+
+Later, when the asynchronous process completes, call either the `Resolve` or `Reject` method on the `Napi::Promise::Deferred` object created earlier:
+
+```cpp
+  deferred.Resolve(String::New(info.Env(), "OK"));
+```
+
+## Promise::Deferred Methods
+
+### Factory Method
+
+```cpp
+static Napi::Promise::Deferred Napi::Promise::Deferred::New(napi_env env);
+```
+
+* `[in] env`: The `napi_env` environment in which to create the `Napi::Promise::Deferred` object.
+
+### Constructor
+
+```cpp
+Napi::Promise::Deferred(napi_env env);
+```
+
+* `[in] env`: The `napi_env` environment in which to construct the `Napi::Promise::Deferred` object.
+
+### Env
+
+```cpp
+Napi::Env Napi::Promise::Deferred::Env() const;
+```
+
+Returns the Env environment this `Napi::Promise::Deferred` object is associated with.
+
+### Promise
+
+```cpp
+Napi::Promise Napi::Promise::Deferred::Promise() const;
+```
+
+Returns the `Napi::Promise` object held by the `Napi::Promise::Deferred` object.
+
+### Resolve
+
+```cpp
+void Napi::Promise::Deferred::Resolve(napi_value value) const;
+```
+
+Resolves the `Napi::Promise` object held by the `Napi::Promise::Deferred` object.
+
+* `[in] value`: The N-API primitive value with which to resolve the `Napi::Promise`.
+
+### Reject
+
+```cpp
+void Napi::Promise::Deferred::Reject(napi_value value) const;
+```
+
+Rejects the Promise object held by the `Napi::Promise::Deferred` object.
+
+* `[in] value`: The N-API primitive value with which to reject the `Napi::Promise`.