strange work of GC

[FG via Digitalmars-d-learn]

On 2015-02-08 at 01:20, Mike Parker wrote:
> In your case, forget destructors and the destroy method. Just implement a common method on all of your objects that need cleanup (perhaps name it 'terminate') and call that. This gives you the deterministic destruction that you want (the same as calling destroy on each object) while avoiding the possibility that the GC can call your cleanup method.

What is wrong with doing all that in a destructor? I don't know if it is just an implementation detail, but a destroyed object is either zero-filled or reinitialized to the default, so, if implemented correctly, it knows whether a cleanup is required (and I'm assuming that a model of simple single ownership is used, like in Qt). Therefore it should be safe to use destroy to finalize an object and even to put destroy in its destructor in order to perform a controlled cascade destruction of all the children that require immediate cleanup (ie. releasing expensive non-GC resources, closing connections, etc.). The main difference with C++ being that you would only force finalization, but then let the GC free the memory in its normal fashion.