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diff --git a/src/result.hpp b/src/result.hpp
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+/*
+ * Copyright (C) 2017 Mentor Graphics Development (Deutschland) GmbH
+ *
+ * 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
+ *
+ *      http://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.
+ */
+
+#ifndef TMCAGLWM_RESULT_HPP
+#define TMCAGLWM_RESULT_HPP
+
+#include <experimental/optional>
+#include <functional>
+
+namespace wm {
+
+using std::experimental::optional;
+using std::experimental::nullopt;
+
+// We only ever return a string as an error - so just parametrize
+// this over result type T
+template <typename T>
+struct result {
+   char const *e;
+   optional<T> t;
+
+   bool is_ok() const { return this->t != nullopt; }
+   bool is_err() const { return this->e != nullptr; }
+
+   T unwrap() {
+      if (this->e != nullptr) {
+         throw std::logic_error(this->e);
+      }
+      return this->t.value();
+   }
+
+   operator T() { return this->unwrap(); }
+
+   char const *unwrap_err() { return this->e; }
+
+   optional<T> const &ok() const { return this->t; }
+   optional<char const *> err() const {
+      return this->e ? optional<char const *>(this->e) : nullopt;
+   }
+
+   result<T> map_err(std::function<char const *(char const *)> f);
+};
+
+template <typename T>
+struct result<T> Err(char const *e) {
+   return result<T>{e, nullopt};
+}
+
+template <typename T>
+struct result<T> Ok(T t) {
+   return result<T>{nullptr, t};
+}
+
+template <typename T>
+result<T> result<T>::map_err(std::function<char const *(char const *)> f) {
+   if (this->is_err()) {
+      return Err<T>(f(this->e));
+   }
+   return *this;
+}
+
+}  // namespace wm
+
+#endif  // TMCAGLWM_RESULT_HPP