+/**
+Loads an object from a file stored in a collection. The object must havea
+public Loader class. The collection is passed to the Loader constructor,
+followed by any extra arguments.
+*/
+template<typename T, typename... Args>
+void load(T &obj, typename T::Loader::Collection &coll, const std::string &fn, Args &... args)
+{
+ RefPtr<IO::Seekable> in = coll.open_raw(fn);
+ if(!in)
+ throw IO::file_not_found(fn);