CTAD issue using frozen::map

[Randalphwa]

Migrated from the original repository
Original issue: serge-sans-paille/frozen#168
Originally reported by: @pfee

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I'm unable to use class template argument deduction (CTAD) with frozen::map and frozen::unordered_map. I'm able to use it with std::map and std::unordered_map.

Is this a bug with the frozen library or an issue with my code?

#include <frozen/set.h>
#include <frozen/map.h>
#include <cstdint> // pmh.h missing include fixed after 1.1.1 was released.
#include <frozen/unordered_map.h>
#include <string_view>
#include <set>
#include <map>
#include <unordered_map>

using namespace std::literals;

int main()
{
    std::set a = {"one"sv, "two"sv};
    frozen::set b = {"one"sv, "two"sv};
    std::map c = {std::pair{"one"sv, 1}, std::pair{"two"sv, 2}};
    // frozen::map d = {std::pair{"one"sv, 1}, std::pair{"two"sv, 2}}; // Compilation error
    std::unordered_map e = {std::pair{"one"sv, 1}, std::pair{"two"sv, 2}};
    // frozen::unordered_map f = {std::pair{"one"sv, 1}, std::pair{"two"sv, 2}}; // Compilation error
    return 0;
}

I've tried compiling with v1.1.1 and with the latest (7e79c375b0) from git. Both fail in the same way.

Environment:

• openSUSE Tumbleweed
• GCC 13.2.1
• C++17

My primary reason for wanting to use CTAD is to avoid having to specify the size of the container, which can be awkward with large datasets.