autoReleasePool function

void autoReleasePool(void function())

Creates an Objective-C autorelease pool, runs function, then releases the pool.

while (longRunningCondiditon) {
  // When writing ObjC interop code inside a long running loop, it's a good
  // idea to use an autorelease pool to clean up autoreleased references.
  autoReleasePool(() {
    // Interacting with most ObjC APIs autoreleases a lot of internal refs.
    final someObjCObject = fooObjCApi.loadNextObject();
    someObjCObject.greet('Hello'.toNSString());
    barObjCApi.sendObject(someObjCObject);
  });
}

This is analogous to the Objective-C @autoreleasepool block:

while (longRunningCondiditon) {
  @autoreleasepool {
    SomeObjCObject *someObjCObject = [fooObjCApi loadNextObject];
    [someObjCObject greet:@"Hello"];
    [barObjCApi sendObject:someObjCObject];
  }
}

function is executed synchronously. Do not try to pass an async function here (the Future it returns will not be awaited). Objective-C autorelease pools form a strict stack, and allowing async execution gaps inside the pool scope could easily break this nesting, so async functions are not supported.

Implementation

void autoReleasePool(void Function() function) {
  final pool = autoreleasePoolPush();
  try {
    function();
  } finally {
    autoreleasePoolPop(pool);
  }
}