X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fcollection.h;h=42dc2c90dd519c7f919742c42aaf1ff40eeee5f7;hb=215e719d0ef85f748898660d15d01e77ac551de9;hp=6ddbe6ed65c980d035b30160ad1eca18c0390f1f;hpb=9c0da3059eed8470325477d99a0d56f0948534fd;p=libs%2Fdatafile.git

diff --git a/source/collection.h b/source/collection.h
index 6ddbe6e..42dc2c9 100644
--- a/source/collection.h
+++ b/source/collection.h
@@ -1,13 +1,14 @@
 /* $Id$
 
 This file is part of libmspdatafile
-Copyright © 2006  Mikko Rasa, Mikkosoft Productions
+Copyright © 2006-2008  Mikko Rasa, Mikkosoft Productions
 Distributed under the LGPL
 */
 
 #ifndef MSP_DATAFILE_COLLECTION_H_
 #define MSP_DATAFILE_COLLECTION_H_
 
+#include <msp/core/meta.h>
 #include <msp/core/refptr.h>
 #include "loader.h"
 
@@ -31,14 +32,6 @@ struct NeedsCollection
 	enum { result=(sizeof(f<T>(0))==sizeof(Yes)) };
 };
 
-template<typename T>
-struct RemoveConst
-{ typedef T Type; };
-
-template<typename T>
-struct RemoveConst<const T>
-{ typedef T Type; };
-
 /**
 A collection of objects that can be loaded from a datafile.  Each object is
 identified by a name, which must be unique across the entire collection.
@@ -72,6 +65,7 @@ private:
 	*/
 	struct ItemKeywordBase
 	{
+		virtual ~ItemKeywordBase() { }
 		virtual void add_to_loader(Loader &) const { };
 	};
 
@@ -105,19 +99,22 @@ private:
 		virtual ~ItemCreatorBase() { }
 
 		template<typename S>
-		S *create(Collection &coll, const std::string &name)
+		bool create(Collection &coll, const std::string &name, S *&ptr)
 		{
 			ItemCreatorBridge<S> *creator=dynamic_cast<ItemCreatorBridge<S> *>(this);
 			if(creator)
-				return creator->create(coll, name);
-			return 0;
+			{
+				ptr=creator->create(coll, name);
+				return true;
+			}
+			return false;
 		}
 	};
 
 	template<typename S>
 	struct ItemCreatorBridge: public ItemCreatorBase
 	{
-		virtual S *create(Collection &, const std::string &) const =0;
+		virtual S *create(Collection &, const std::string &) const = 0;
 	};
 
 	template<typename T, typename S, typename C>
@@ -189,7 +186,7 @@ public:
 	void add(const std::string &name, T *d)
 	{
 		if(items.count(name))
-			throw KeyError("Duplicate key '"+name+"' in collection");
+			throw KeyError("Duplicate key in collection", name);
 
 		items[name]=new Item<typename RemoveConst<T>::Type>(d);
 	}
@@ -198,19 +195,19 @@ public:
 	Gets an object of a specific type from the collection.
 	*/
 	template<typename T>
-	T &get(const std::string &name) const
+	T *get(const std::string &name) const
 	{
 		typedef typename RemoveConst<T>::Type NCT;
 
 		ItemMap::const_iterator i=items.find(name);
 		if(i==items.end())
-			throw KeyError("Item '"+name+"' not found in collection");
+			throw KeyError("Item not found in collection", name);
 
 		const Item<NCT> *item=dynamic_cast<const Item<NCT> *>(i->second);
 		if(!item)
-			throw TypeError("Item '"+name+"' is not of correct type");
+			throw TypeError("Type mismatch on item '"+name+"'");
 
-		return *item->data;
+		return item->data;
 	}
 
 	/**
@@ -219,7 +216,7 @@ public:
 	invoked.
 	*/
 	template<typename T>
-	T &get(const std::string &name)
+	T *get(const std::string &name)
 	{
 		typedef typename RemoveConst<T>::Type NCT;
 
@@ -227,20 +224,23 @@ public:
 		if(i==items.end())
 		{
 			for(ItemCreatorSeq::iterator j=creators.begin(); j!=creators.end(); ++j)
-				if(NCT *d=(*j)->create<NCT>(*this, name))
+			{
+				NCT *d=0;
+				if((*j)->create(*this, name, d))
 				{
 					// We already know that the item didn't exist yet
 					items[name]=new Item<NCT>(d);
-					return *d;
+					return d;
 				}
-			throw KeyError("Item '"+name+"' not found in collection");
+			}
+			throw KeyError("Item not found in collection", name);
 		}
 
 		const Item<NCT> *item=dynamic_cast<const Item<NCT> *>(i->second);
 		if(!item)
-			throw TypeError("Item '"+name+"' is not of correct type");
+			throw TypeError("Type mismatch on item '"+name+"'");
 
-		return *item->data;
+		return item->data;
 	}
 
 	/**
@@ -277,6 +277,22 @@ public:
 	*/
 	bool contains(const std::string &n) const;
 
+	/**
+	Returns the name of an item in the collection.
+	*/
+	template<typename T>
+	const std::string &get_name(T *d) const
+	{
+		typedef typename RemoveConst<T>::Type NCT;
+
+		for(ItemMap::const_iterator i=items.begin(); i!=items.end(); ++i)
+			if(Item<NCT> *item=dynamic_cast<Item<NCT> *>(i->second))
+				if(item->data==d)
+					return i->first;
+	
+		throw KeyError("Item not found in collection");
+	}
+
 protected:
 	/**
 	Adds a type that can be loaded from datafiles.