From 6678cf025ca97dd398a9304b0578f146d1f7af80 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 2 Nov 2007 19:43:21 +0000
Subject: [PATCH] Change Collection interface to use pointers consistently Make
 it possible for creators to return 0 pointers successfully Add LoaderFunc5

---
 source/collection.h | 20 +++++++++++++-------
 source/loader.h     | 21 +++++++++++++++++++++
 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/source/collection.h b/source/collection.h
index 6ddbe6e..24be69d 100644
--- a/source/collection.h
+++ b/source/collection.h
@@ -105,19 +105,22 @@ 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;
+			{
+				creator->create(coll, name, ptr);
+				return true;
+			}
+			return false;
 		}
 	};
 
 	template<typename S>
 	struct ItemCreatorBridge: public ItemCreatorBase
 	{
-		virtual S *create(Collection &, const std::string &) const =0;
+		virtual bool create(Collection &, const std::string &, S *&) const =0;
 	};
 
 	template<typename T, typename S, typename C>
@@ -198,7 +201,7 @@ 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;
 
@@ -219,7 +222,7 @@ public:
 	invoked.
 	*/
 	template<typename T>
-	T &get(const std::string &name)
+	T *get(const std::string &name)
 	{
 		typedef typename RemoveConst<T>::Type NCT;
 
@@ -227,12 +230,15 @@ 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;
 				}
+			}
 			throw KeyError("Item '"+name+"' not found in collection");
 		}
 
diff --git a/source/loader.h b/source/loader.h
index 8d26a41..acc84fe 100644
--- a/source/loader.h
+++ b/source/loader.h
@@ -151,6 +151,23 @@ private:
 };
 
 
+template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+class LoaderFunc5: public LoaderAction
+{
+public:
+	typedef void (L::*FuncType)(A0, A1, A2, A3, A4);
+
+	LoaderFunc5(FuncType f): func(f) { }
+	void execute(Loader &l, const Statement &st) const
+	{
+		if(st.args.size()!=5) throw TypeError(st.get_location()+": Wrong number of arguments");
+		(dynamic_cast<L &>(l).*func)(st.args[0].get<A0>(), st.args[1].get<A1>(), st.args[2].get<A2>(), st.args[3].get<A3>(), st.args[4].get<A4>());
+	}
+private:
+	FuncType func;
+};
+
+
 template<typename L, typename T0>
 class LoadValue1: public LoaderAction
 {
@@ -257,6 +274,10 @@ protected:
 	void add(const std::string &k, void (L::*func)(A0, A1, A2, A3))
 	{ add(k, new LoaderFunc4<L, A0, A1, A2, A3>(func)); }
 
+	template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+	void add(const std::string &k, void (L::*func)(A0, A1, A2, A3, A4))
+	{ add(k, new LoaderFunc5<L, A0, A1, A2, A3, A4>(func)); }
+
 	/**
 	Adds a keyword that is loaded into a variable of the loaded object.
 	*/
-- 
2.43.0