Throw an exception if a future object couldn't be created

[libs/datafile.git] / source / collection.h

diff --git a/source/collection.h b/source/collection.h
index 3d5b7f0a6abce95bc8aa5d6ec05749be3ec6f8b2..c83b4376d20b2b6d4854b29dfc0fbda9c0c286b5 100644 (file)
--- a/source/collection.h
+++ b/source/collection.h
@@ -130,8 +130,14 @@ protected:
                insert_unique(items, name, ptr);
        }
 
+       /** Adds the name of a future object, guessing its type.  If a type matching
+       the name can't be found, nothing is done. */
        void add_future(const std::string &name);
 
+       /** Adds the name of a future object, using a keyword to determine its type.
+       The keyword must be known to the collection. */
+       void add_future_with_keyword(const std::string &name, const std::string &);
+
 public:
        /// Gets a typed object from the collection.
        template<typename T>
@@ -308,11 +314,12 @@ public:
        virtual ~CollectionItemTypeBase();
 
        void set_keyword(const std::string &);
+       const std::string &get_keyword() const { return kwd; }
        void add_suffix(const std::string &);
+       bool match_name(const std::string &) const;
        virtual void add_to_loader(Collection::Loader &) const = 0;
        virtual bool can_create() const = 0;
        virtual void create_item(Collection &, const std::string &) const = 0;
-       bool match_name(const std::string &) const;
        virtual Variant create_future() const = 0;
 
        template<typename T>
@@ -478,7 +485,10 @@ T &Collection::get(const std::string &name)
                if((*j)->can_create() && (*j)->check_type<NCT>())
                        (*j)->create_item(*this, name);
 
-       return *get_item(items, name).value<RefPtr<NCT> >();
+       NCT *ptr = get_item(items, name).value<RefPtr<NCT> >().get();
+       if(!ptr)
+               throw key_error(typeid(ItemMap));
+       return *ptr;
 }
 
 template<typename T>