3 ms·

It's a sad example of my C++ knowledge that I didn't know about the checked add intrinsics, but I do know that unsigned (x + y) < x compiles into checking the c

• SideQuark 2y ago
  Those are compiler specific intrinsics, not standard C++. It's pretty easy to make a checked integer (or float) math lib/type in C++. Make a class that holds an int, overload the ops, check them. I regularly do such stuff when proving boundedness of algorithms, or performance of an algorithm. Such a class can track numbers of adds, mults, etc., can catch errors, can track values of stats, anything. I also made and regularly use an IntN type: the idea is take half the max int size your system has natively, say IntN, and make a Int2N built by hand as a class. Now templateize it on size. Now you can recursively make Int2N, 4N, 8N, etc., from that template, basically for free (no more code needed), and have any size int. There's a lot of cool numerics stuff you can do along these lines.