https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103924
Bug ID: 103924
Summary: views::join combined with std::string cannot be used
in constant expressions
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: hewillk at gmail dot com
Target Milestone: ---
The following code cannot be used as a constant expression, but it should work
since constexpr non-propagating-cache and std::string have been implemented.
#include <string>
#include <ranges>
int main() {
using namespace std::string_literals;
static_assert(std::ranges::distance(
std::views::single("42"s) | std::views::join));
}
https://godbolt.org/z/zPv4xnxnP
#include <string>
#include <ranges>
int main() {
using namespace std::string_literals;
static_assert(std::ranges::distance(
std::views::iota(0, 1)
| std::views::transform([](auto) { return "42"s; })
| std::views::join));
}
https://godbolt.org/z/d5TM4x53z
