basic_iterator does not have operator->

[subbota-a]

std::map<int, std::wstring> ss;
auto rng = ss | ranges::view::values;
auto it = ranges::find_if(rng, [](auto&& x){ x == 10;});
int y = it.base()->first; // this does not compile
// but this OK
// int z = (*(it.base())).first;

[Holt59]

Related commit in range-v3: https://github.com/ericniebler/range-v3/commit/d67cc2c00f0b4ad27829383d7e71cd7d8a5714e5#diff-25aaca5db1ccdc152d5b5605c64df24f