+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