New Expected template (should have been included in a previous commit)

src/Helpers/Expected.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <variant>
+#include <type_traits>
+
+template<typename SuccessType, typename ErrorType>
+struct Expected
+{
+    Expected(SuccessType&& result)
+        requires (
+            !std::is_reference_v<SuccessType>
+            && !std::is_fundamental_v<SuccessType>
+        )
+        : result(std::move(result))
+    {}
+
+    Expected(const SuccessType& result)
+        : result(result)
+    {}
+
+    Expected(const ErrorType& result)
+        : result(result)
+    {}
+
+    bool hasValue() const {
+        return std::holds_alternative<SuccessType>(this->result);
+    }
+
+    const SuccessType& value() const {
+        return std::get<SuccessType>(this->result);
+    }
+
+    const ErrorType& error() const {
+        return std::get<ErrorType>(this->result);
+    }
+
+private:
+    std::variant<SuccessType, ErrorType> result;
+};