1 files changed, 14 insertions, 1 deletions
diff --git a/include/cru/common/Bitmask.h b/include/cru/common/Bitmask.h
index bd6a8309..b1e8495e 100644
--- a/include/cru/common/Bitmask.h
+++ b/include/cru/common/Bitmask.h
@@ -1,6 +1,8 @@
 #pragma once
 #include "Base.h"
 
+#include <functional>
+
 namespace cru {
 template <typename Tag, typename TUnderlying = unsigned>
 struct Bitmask final {
@@ -35,8 +37,19 @@ struct Bitmask final {
   bool operator!=(Bitmask rhs) const { return this->value != rhs.value; }
 
   explicit operator TUnderlying() const { return value; }
-  operator bool() const { return value != 0; }
+  explicit operator bool() const { return value != 0; }
 
   TUnderlying value;
 };
 }  // namespace cru
+
+namespace std {
+template <typename Tag, typename TUnderlying>
+struct hash<cru::Bitmask<Tag, TUnderlying>> {
+  using Bitmask = cru::Bitmask<Tag, TUnderlying>;
+
+  std::size_t operator()(Bitmask bitmask) const {
+    return std::hash<TUnderlying>{}(bitmask.value);
+  }
+};
+}  // namespace std