Pass a block as a void pointer in ARC

Example.m

- (void)delete
{
	void (^myBlock)() = ^{/*some block action*/};

	NSBeginCriticalAlertSheet(NSLocalizedString(@"ReallyDeleteWarning", nil),
				NSLocalizedString(@"Delete", nil),
				NSLocalizedString(@"Cancel", nil), nil, self.window, self, nil,
				@selector(deleteAlertWindow:didDismissWithCode:context:),
				(__bridge_retained void *)([myBlock copy]),
				NSLocalizedString(@"ReallyDeleteWarningMsg", nil));
}

- (void)deleteAlertWindow:(NSWindow *)sheet didDismissWithCode:(NSInteger)code context:(void *)ctx//(void (^)(void))block
{
	void (^myBlock)() = (__bridge_transfer typeof(myBlock))ctx;
	if (code == NSAlertDefaultReturn)
	{
		if (myBlock != nil)
			myBlock();
	}
}