tdesktop/Telegram/ThirdParty/range-v3/TODO.md

• Add contiguous iterator utilities. How about is_contiguous_iterator and as_contiguous_range:

  CPP_template(typename I, typename S)(
      requires RandomAccessIterator<I> &&
          SizedSentinel<S, I> &&
          is_contiguous_iterator<I>())
  subrange<std::add_pointer_t<iter_reference_t<I>>>
  as_contiguous_range(I begin, S end)
  {
      if(begin == end)
          return {nullptr, nullptr};
      else
          return {addressof(*begin), addressof(*begin) + (end - begin)};
  }
  

• Longer-term goals:

  • Make inplace_merge work with forward iterators
  • Make the sorting algorithms work with forward iterators

• Maybe iterators are not necessarily countable. Is there a relation between the ability to be able to subtract two iterators to find the distance, and with the existence of a DistanceType associated type? Think of:

  • counted iterators (subtractable regardless of traversal category)
  • repeat_view iterators (not subtractable but could be random access otherwise)
  • infinite ranges (only countable with an infinite precision integer which we lack)