add more utilities

rx/include/rx/atScopeExit.hpp

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <utility>
+
+namespace rx {
+template <typename T> class atScopeExit {
+  T _object;
+
+public:
+  atScopeExit(T &&object) : _object(std::forward<T>(object)) {}
+  ~atScopeExit() { _object(); }
+};
+} // namespace rx

rx/include/rx/die.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+namespace rx {
+[[noreturn, gnu::format(printf, 1, 2)]] void die(const char *message, ...);
+[[gnu::format(printf, 2, 3)]] void dieIf(bool condition, const char *message,
+                                         ...);
+} // namespace rx