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diff --git a/src/third-party/scnlib/include/scn/util/expected.h b/src/third-party/scnlib/include/scn/util/expected.h
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+++ b/src/third-party/scnlib/include/scn/util/expected.h
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+// Copyright 2017 Elias Kosunen
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// This file is a part of scnlib:
+//     https://github.com/eliaskosunen/scnlib
+
+#ifndef SCN_UTIL_EXPECTED_H
+#define SCN_UTIL_EXPECTED_H
+
+#include "memory.h"
+
+namespace scn {
+    SCN_BEGIN_NAMESPACE
+
+    /**
+     * expected-like type.
+     * For situations where there can be a value in case of success or an error
+     * code.
+     */
+    template <typename T, typename Error, typename Enable>
+    class expected;
+
+    /**
+     * expected-like type for default-constructible success values.
+     * Not optimized for space-efficiency (both members are stored
+     * simultaneously).
+     * `error` is used as the error value and discriminant flag.
+     */
+    template <typename T, typename Error>
+    class expected<T,
+                   Error,
+                   typename std::enable_if<
+                       std::is_default_constructible<T>::value>::type> {
+    public:
+        using success_type = T;
+        using error_type = Error;
+
+        constexpr expected() = default;
+        constexpr expected(success_type s) : m_s(s) {}
+        constexpr expected(error_type e) : m_e(e) {}
+
+        SCN_NODISCARD constexpr bool has_value() const noexcept
+        {
+            return m_e == Error{};
+        }
+        constexpr explicit operator bool() const noexcept
+        {
+            return has_value();
+        }
+        constexpr bool operator!() const noexcept
+        {
+            return !operator bool();
+        }
+
+        SCN_CONSTEXPR14 success_type& value() & noexcept
+        {
+            return m_s;
+        }
+        constexpr success_type value() const& noexcept
+        {
+            return m_s;
+        }
+        SCN_CONSTEXPR14 success_type value() && noexcept
+        {
+            return SCN_MOVE(m_s);
+        }
+
+        SCN_CONSTEXPR14 error_type& error() noexcept
+        {
+            return m_e;
+        }
+        constexpr error_type error() const noexcept
+        {
+            return m_e;
+        }
+
+    private:
+        success_type m_s{};
+        error_type m_e{error_type::success_tag()};
+    };
+
+    /**
+     * expected-like type for non-default-constructible success values.
+     * Not optimized for space-efficiency.
+     * `error` is used as the error value and discriminant flag.
+     */
+    template <typename T, typename Error>
+    class expected<T,
+                   Error,
+                   typename std::enable_if<
+                       !std::is_default_constructible<T>::value>::type> {
+    public:
+        using success_type = T;
+        using success_storage = detail::erased_storage<T>;
+        using error_type = Error;
+
+        expected(success_type s) : m_s(SCN_MOVE(s)) {}
+        constexpr expected(error_type e) : m_e(e) {}
+
+        SCN_NODISCARD constexpr bool has_value() const noexcept
+        {
+            return m_e == Error{};
+        }
+        constexpr explicit operator bool() const noexcept
+        {
+            return has_value();
+        }
+        constexpr bool operator!() const noexcept
+        {
+            return !operator bool();
+        }
+
+        SCN_CONSTEXPR14 success_type& value() noexcept
+        {
+            return *m_s;
+        }
+        constexpr const success_type& value() const noexcept
+        {
+            return *m_s;
+        }
+
+        SCN_CONSTEXPR14 error_type& error() noexcept
+        {
+            return m_e;
+        }
+        constexpr error_type error() const noexcept
+        {
+            return m_e;
+        }
+
+    private:
+        success_storage m_s{};
+        error_type m_e{error_type::success_tag()};
+    };
+
+    template <typename T,
+              typename U = typename std::remove_cv<
+                  typename std::remove_reference<T>::type>::type>
+    expected<U> make_expected(T&& val)
+    {
+        return expected<U>(std::forward<T>(val));
+    }
+
+    SCN_END_NAMESPACE
+}  // namespace scn
+
+#endif