2 files changed, 13 insertions, 4 deletions
diff --git a/include/cru/common/Base.hpp b/include/cru/common/Base.hpp
index a5a9421d..560f83bb 100644
--- a/include/cru/common/Base.hpp
+++ b/include/cru/common/Base.hpp
@@ -1,8 +1,8 @@
 #pragma once
 #include "PreConfig.hpp"
 
+#include <exception>
 #include <gsl/gsl>
-
 #include <stdexcept>
 
 #define CRU_UNUSED(entity) static_cast<void>(entity);
@@ -42,12 +42,17 @@ struct Interface {
   virtual ~Interface() = default;
 };
 
-[[noreturn]] inline void UnreachableCode() {
-  throw std::runtime_error("Unreachable code.");
-}
+[[noreturn]] inline void UnreachableCode() { std::terminate(); }
 
 using Index = gsl::index;
 
+// https://www.boost.org/doc/libs/1_54_0/doc/html/hash/reference.html#boost.hash_combine
+template <class T>
+inline void hash_combine(std::size_t& s, const T& v) {
+  std::hash<T> h;
+  s ^= h(v) + 0x9e3779b9 + (s << 6) + (s >> 2);
+}
+
 #define CRU_DEFINE_CLASS_LOG_TAG(tag) \
  private:                             \
   constexpr static std::u16string_view log_tag = tag;
diff --git a/include/cru/common/Event.hpp b/include/cru/common/Event.hpp
index 6417bc78..93ab9b7a 100644
--- a/include/cru/common/Event.hpp
+++ b/include/cru/common/Event.hpp
@@ -232,6 +232,10 @@ class EventRevokerListGuard {
     return *this;
   }
 
+  void Clear() { event_revoker_guard_list_.clear(); }
+
+  bool IsEmpty() const { return event_revoker_guard_list_.empty(); }
+
  private:
   std::vector<EventRevokerGuard> event_revoker_guard_list_;
 };