static I impl()

in include/range/v3/algorithm/search_n.hpp [89:118]

• 28 lines of code
• 9 McCabe index (conditional complexity)

            static I impl(I begin, S end, D count, V const &val, C &pred, P &proj)
            {
                while(true)
                {
                    // Find begin element in sequence 1 that matches val, with a mininum of loop checks
                    while(true)
                    {
                        if(begin == end)  // return end if no element matches val
                            return begin;
                        if(pred(proj(*begin), val))
                            break;
                        ++begin;
                    }
                    // *begin matches val, now match elements after here
                    I m = begin;
                    D c = 0;
                    while(true)
                    {
                        if(++c == count)  // If pattern exhausted, begin is the answer (works for 1 element pattern)
                            return begin;
                        if(++m == end)  // Otherwise if source exhausted, pattern not found
                            return m;
                        if(!pred(proj(*m), val))  // if there is a mismatch, restart with a new begin
                        {
                            begin = next(std::move(m));
                            break;
                        }  // else there is a match, check next elements
                    }
                }
            }