Support seed type different from std::size_t for hashCombine

components/misc/hash.hpp

@@ -1,15 +1,20 @@
 #ifndef MISC_HASH_H
 #define MISC_HASH_H
 
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+
 namespace Misc
 {
     /// Implemented similar to the boost::hash_combine
-    template <class T>
-    inline void hashCombine(std::size_t& seed, const T& v)
+    template <class Seed, class T>
+    inline void hashCombine(Seed& seed, const T& v)
     {
+        static_assert(sizeof(Seed) >= sizeof(std::size_t), "Resulting hash will be truncated");
         std::hash<T> hasher;
-        seed ^= hasher(v) + 0x9e3779b9 + (seed<<6) + (seed>>2);
+        seed ^= static_cast<Seed>(hasher(v) + 0x9e3779b9 + (seed<<6) + (seed>>2));
     }
 }
 
-#endif
+#endif