No, accumulate is a perfectly reasonable algorithm, and it’s not made obsolete by any other algorithm. The reason for it not being included in C++20 is simply a matter of time. It was considered better to add as much as possible with regards to ranges, without worrying about adding everything at once. Otherwise, there was … Read more
It looks like there are now test cases in the range-v3 library that show how to do this correctly. It is necessary to add the views::cache1 operator into the pipeline: auto rng = views::iota(0,4) | views::transform([](int i) {return std::string(i, char(‘a’+i));}) | views::cache1 | views::join(‘-‘); check_equal(rng, {‘-‘,’b’,’-‘,’c’,’c’,’-‘,’d’,’d’,’d’}); CPP_assert(input_range<decltype(rng)>); CPP_assert(!range<const decltype(rng)>); CPP_assert(!forward_range<decltype(rng)>); CPP_assert(!common_range<decltype(rng)>); so the solutions for … Read more