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diff --git a/src/catch2/internal/catch_container_nonmembers.hpp b/src/catch2/internal/catch_container_nonmembers.hpp
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+++ b/src/catch2/internal/catch_container_nonmembers.hpp
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+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+#ifndef CATCH_CONTAINER_NONMEMBERS_HPP_INCLUDED
+#define CATCH_CONTAINER_NONMEMBERS_HPP_INCLUDED
+
+#include <catch2/internal/catch_compiler_capabilities.hpp>
+
+#include <cstddef>
+#include <initializer_list>
+
+// We want a simple polyfill over `std::empty`, `std::size` and so on
+// for C++14 or C++ libraries with incomplete support.
+// We also have to handle that MSVC std lib will happily provide these
+// under older standards.
+#if defined(CATCH_CPP17_OR_GREATER) || defined(_MSC_VER)
+
+// We are already using this header either way, so there shouldn't
+// be much additional overhead in including it to get the feature
+// test macros
+#include <string>
+
+#  if !defined(__cpp_lib_nonmember_container_access)
+#      define CATCH_CONFIG_POLYFILL_NONMEMBER_CONTAINER_ACCESS
+#  endif
+
+#else
+#define CATCH_CONFIG_POLYFILL_NONMEMBER_CONTAINER_ACCESS
+#endif
+
+
+
+namespace Catch {
+namespace Detail {
+
+#if defined(CATCH_CONFIG_POLYFILL_NONMEMBER_CONTAINER_ACCESS)
+    template <typename Container>
+    constexpr auto empty(Container const& cont) -> decltype(cont.empty()) {
+        return cont.empty();
+    }
+    template <typename T, std::size_t N>
+    constexpr bool empty(const T (&)[N]) noexcept {
+        // GCC < 7 does not support the const T(&)[] parameter syntax
+        // so we have to ignore the length explicitly
+        (void)N;
+        return false;
+    }
+    template <typename T>
+    constexpr bool empty(std::initializer_list<T> list) noexcept {
+        return list.size() > 0;
+    }
+
+
+    template <typename Container>
+    constexpr auto size(Container const& cont) -> decltype(cont.size()) {
+        return cont.size();
+    }
+    template <typename T, std::size_t N>
+    constexpr std::size_t size(const T(&)[N]) noexcept {
+        return N;
+    }
+#endif // CATCH_CONFIG_POLYFILL_NONMEMBER_CONTAINER_ACCESS
+
+} // end namespace Detail
+} // end namespace Catch
+
+
+
+#endif // CATCH_CONTAINER_NONMEMBERS_HPP_INCLUDED