I guess you've already checked the iterator requirements, but just in case; it's basically implementing everything on this page (and the "named requirements" pages linked from it): https://en.cppreference.com/w/cpp/named_req/RandomAccessIterator

The various iterator_traits typedefs are usually defined directly in the iterator class. The unspecialized iterator_traits just redirects to typedefs defined in the class.

These types should then be used for the return values of the various iterator functions, e.g.

 difference_type operator-(const RecordIterator& it) const noexcept {
     return m_component_it - it.m_component_it;
 }

Note: this originally returned std::size_t. However, the difference_type must be signed (std::ptrdiff_t is correct). The other mathematical operations have the same issue.

Unfortunately, we actually need pointer and reference typedefs, not pointer_type and reference_type.

I don't think it's actually possible to fulfill the exact requirements for the reference type (ForwardIterator requires it to be T& or T const& where T is value_type). Defining it as Record<T> should work correctly in most cases though.

For pointer, you might simply define it as void, leave the arrow operator undefined, and see if anything breaks. This answer on stackoverflow implies that reference and pointer aren't used inside the algorithms themselves, so you should be ok. Perhaps someone else with more knowledge can weigh in on this.

I guess you've already checked the iterator requirements, but just in case; it's basically implementing everything on this page (and the "named requirements" pages linked from it): https://en.cppreference.com/w/cpp/named_req/RandomAccessIterator

The various iterator_traits typedefs are usually defined directly in the iterator class. The unspecialized version of iterator_traits just redirects to typedefs defined in the class.

These types should then be used for the return values of the various iterator functions, e.g.

 difference_type operator-(const RecordIterator& it) const noexcept {
     return m_component_it - it.m_component_it;
 }

Note: this originally returned std::size_t. However, the difference_type must be signed (std::ptrdiff_t is correct). The other mathematical operations have the same issue.

Unfortunately, we actually need pointer and reference typedefs, not pointer_type and reference_type.

I don't think it's possible to fulfill the exact requirements for the reference type (ForwardIterator requires it to be T& or T const& where T is value_type). Defining it as Record<T> should work correctly in most cases though.

For pointer, you might simply define it as void, leave the arrow operator undefined, and see if anything breaks. This answer on stackoverflow implies that reference and pointer aren't used inside the algorithms themselves, so you should be ok. Perhaps someone else with more knowledge can weigh in on this.