SSO-23

code. Why? The C++ solution uses uses operator+ which is fundamentally performing a different and less general algorithm. For composition it will introduce some amount of repeated work which even the best link-time optimizing compilers probably won't remove, and may, depending on the length of the trailing string segments, and the growth strategy used under the covers, force two allocations. The standard doesn't give complexity guarantees for mutation on std::string at all, so the resulting performance could, on some platforms, be very bad. In all cases you will be able to construct an input that forces more than one allocation (exponentially growing segment sizes). There's also another efficiency issue in the naive op+ approach... C++s allocator specification doesn't provide realloc() so a portable solution will always use more peak memory, on average, when it is forced to reallocate. The C++ solution is just using the wrong algorithm for the job. You can write, and I have toyed with[1], a variadic strcat() function that will be optimal in the generic case. The standard library just lacks one. It's embarrassing, but fairly understandable given that variadic templates didn't come in to the standard until 2011. I'm hoping if they introduce one it'll be called scat() :-) I'm a big C++ fan, but we shouldn't be deluding ourselves here. Fortunately, these things can be fixed within the framework of the current language. [0] https://github.com/elliotgoodrich/SSO-23/blob/master/README.... [1] http://codepad.org/rkmNTkIn