<format>: in_range apply on non-integrals triggers a static_assert #5182
Description
Yap, another annoying difference-type issue.
Lines 3283 to 3290 in 89ca073
_Size may be of integer-class type such as _Signed128, which currently does not work with in_range as it Mandates standard or extended integer types:
#include <ranges>
#include <print>
struct ContiguousIter {
using iterator_category = std::contiguous_iterator_tag;
using difference_type = std::_Signed128;
using element_type = char;
element_type& operator*() const;
ContiguousIter& operator++();
ContiguousIter operator++(int);
ContiguousIter& operator--();
ContiguousIter operator--(int);
ContiguousIter& operator+=(difference_type);
ContiguousIter& operator-=(difference_type);
element_type* operator->() const;
element_type& operator[](difference_type) const;
friend ContiguousIter operator+(ContiguousIter, difference_type);
friend ContiguousIter operator+(difference_type, ContiguousIter);
friend ContiguousIter operator-(ContiguousIter, difference_type);
friend difference_type operator-(ContiguousIter, ContiguousIter);
auto operator<=>(const ContiguousIter&) const = default;
};
int main() {
ContiguousIter it;
std::ranges::contiguous_range auto r = std::ranges::subrange(it, it + 42);
std::println("{:s}", r); // fire
}Note that this is not reproducible on Godbolt as the STL version used by MSVC does not yet support formatting ranges. (Is there any way to reproduce this online?)