Is there a trait or some convention to check if there is a range or `view_facade` that owns things? (e.g. getlines)

Question

Considering

auto empty_line = [](auto& str){ return str.size() == 0; }; 

For ranges::getlines returns the ranges::getlines property, which owns the buffer for its frontal iterator.

So, we are supposed to make this range of values ​​before moving on to algorithms.

 auto line_range1 = ranges::getlines(std::cin); auto iter1 = ranges::find_if_not(line_range1,empty_line); auto input1 = std::stoi(*iter1); 

And also there is a cool defensive machinism that prevents all dereferencing of iterators in time of already destroyed data and made these attempts by compiling time errors.

Therefore, when the owner of view_facade is passed to the algorithm as an rvalue, protection is captured when dereferencing.

This will not compile.

 auto iter2 = ranges::find_if_not(ranges::getlines(std::cin),empty_line); // at this point the `owning` range destroyed, // so as the buffer we (should've) hold (before!). // So this won't compile // auto input2 = std::stoi(*iter2); 

Mistake:

 <source>:19:29: error: no match for 'operator*' (operand type is 'ranges::v3::dangling<ranges::v3::_basic_iterator_::basic_iterator<ranges::v3::getlines_range::cursor> >') auto input2 = std::stoi(*iter2); ^~~~~~ 

It will also not compile.

 // Won't compile // auto input3 = std::stoi(*ranges::find_if_not(ranges::getlines(std::cin), // empty_line) // ); 

Mistake:

 <source>:22:29: error: no match for 'operator*' (operand type is 'ranges::v3::safe_iterator_t<ranges::v3::getlines_range> {aka ranges::v3::dangling<ranges::v3::_basic_iterator_::basic_iterator<ranges::v3::getlines_range::cursor> >}') auto input3 = std::stoi(*ranges::find_if_not(ranges::getlines(std::cin),empty_line)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

godbolt.org/g/gF6nYx

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My question is, besides the documentation, are there any traits or any range convention to check if the range type owns?

Maybe something like constexpr bool is_owning_v(Rng&&)