Elegant way to execute code on function exit in Dart-CodePudding

Suppose we need to execute some code when a function finishes, no matter how. Example:

void myFunc() async {
    await myLock.acquire();
    if(...) {
        myLock.release();
        return;
    }
    ...
    myLock.release();
}

Many languages have features that allow to achieve this in a more elegant way than just manually calling myLock.release() before every return statement (For example defer in Go). Is something like that also possible in Dart?

CodePudding user response：

Dart does not have RAII. You instead would need to use try-finally.

(Dart did recently (in 2.17) add Finalizers, but those would fire when objects are garbage collected, which might happen at some non-deterministic time, if ever.)

CodePudding user response：

And just for the record, an example of using try/finally:

void myFunc() async {
  await myLock.acquire();
  try {
    if(...) {
        return;
    }  
    ...
  } finally {
    myLock.release();
  }
 
}

You'd want to start the try after allocating the resource, so that you don't try to release if allocation throws.