13 thoughts on “#facepalm of the day

  1. Lars Fosdal Well the main idea is that you can’t access/manipulate the list items except through the interface returned from the Lock() method. The “synchronized access interface” will unlock when it goes out of scope.

    So in your case, the code would become:


    listAccess: IListAccess;


    listAccess := ListA.Lock();

    listAccess.Add(…); // or whatever you want

    end; // list is unlocked when listAccess goes out of scope or is nilled

    This way you cannot lock the wrong list (compared to the one you’re manipulating).

    So IListAccess would have most of the methods, while IThreadSafeList (or whatever ListA is) would basically just have Lock() and possibly some helper methods if needed.

    Guess maybe a generic wrapper could be possible with a bit of voodoo.

  2. Language support is the way here. Heap allocation of an object to implement an interface is overkill. Or you could just get the code right in the first place. I’d take that over darn ref counting.