`std::vector` is often said to be the default container, because it provides good baseline performance for common operations. Recently, I experimented with a simple API change that can improve the performance of a common usage pattern by 10+ %.
  • potterman28wxcv@beehaw.org
    21·
    2 years ago

    Then you have to ask yourself, is it worth it to add yet another function that can crash your program if misused just for that 10% in a situation where they might not even matter

    C/C++ already exposes a ton of undefined behaviors: it is part of the language to give full control to the programmer. If you want a language that minimizes the number of undefined behaviors you can get into, C/C++ is not the right candidate anyway. Something like Ada or Rust is much more relevant for that.

    So I would say yes, just as long as it is properly documented.

    • CasualTee@beehaw.org
      3·
      2 years ago

      I disagree. The question is not really “should we give programmer more power at the cost of yet another UB” but more “should we grow the API and add another UB for the select few for whom it might matter”. When you consider choices made on other parts of the STL, such as std::unordered_map, then you realize the STL is not about being the most performant things around, but rather a collection of reliable tools covering basic usage for 80% of the user base.

      With that in mind, I am against adding yet another function, which has its pitfalls, for minimal benefits. Again, such a function would be made almost entirely obsolete by a safe function that works with iterators/generators of known sizes. So I see even less benefit in adding a function that will just become yet another liability down the line.