Start CMake modernization scaffold

src/foundation/result.h

@@ -0,0 +1,80 @@
+#pragma once
+
+namespace pp::foundation {
+
+enum class StatusCode {
+    ok,
+    invalid_argument,
+    out_of_range,
+};
+
+struct Status {
+    StatusCode code = StatusCode::ok;
+    const char* message = "ok";
+
+    [[nodiscard]] constexpr bool ok() const noexcept
+    {
+        return code == StatusCode::ok;
+    }
+
+    [[nodiscard]] static constexpr Status success() noexcept
+    {
+        return {};
+    }
+
+    [[nodiscard]] static constexpr Status invalid_argument(const char* message) noexcept
+    {
+        return { StatusCode::invalid_argument, message };
+    }
+
+    [[nodiscard]] static constexpr Status out_of_range(const char* message) noexcept
+    {
+        return { StatusCode::out_of_range, message };
+    }
+};
+
+template <typename T>
+class Result {
+public:
+    [[nodiscard]] static constexpr Result success(T value) noexcept
+    {
+        return Result(value, Status::success());
+    }
+
+    [[nodiscard]] static constexpr Result failure(Status status) noexcept
+    {
+        return Result(T{}, status);
+    }
+
+    [[nodiscard]] constexpr bool ok() const noexcept
+    {
+        return status_.ok();
+    }
+
+    [[nodiscard]] constexpr explicit operator bool() const noexcept
+    {
+        return ok();
+    }
+
+    [[nodiscard]] constexpr const T& value() const noexcept
+    {
+        return value_;
+    }
+
+    [[nodiscard]] constexpr Status status() const noexcept
+    {
+        return status_;
+    }
+
+private:
+    constexpr Result(T value, Status status) noexcept
+        : value_(value)
+        , status_(status)
+    {
+    }
+
+    T value_{};
+    Status status_{};
+};
+
+}