From 645ddd284c32084283291f928b97f3d3c035505c Mon Sep 17 00:00:00 2001
From: Ichthyostega <prg@ichthyostega.de>
Date: Thu, 25 Nov 2010 04:52:49 +0100
Subject: [PATCH] WIP Solution draft for defining an output mapping type

---
 src/lib/meta/duck-detector.hpp      |  2 +-
 src/proc/assetmanager.cpp           | 11 ++++++-----
 src/proc/mobject/output-mapping.hpp | 21 ++++++++++++---------
 3 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/src/lib/meta/duck-detector.hpp b/src/lib/meta/duck-detector.hpp
index 70bec2a18..9ee864880 100644
--- a/src/lib/meta/duck-detector.hpp
+++ b/src/lib/meta/duck-detector.hpp
@@ -41,7 +41,7 @@
  ** 
  ** Most of these trait templates rely on a creative use of function overloading. The C++ standard
  ** requires the compiler <i>silently to drop</i> any candidate of overload resolution which has
- ** gotten an invalid function signature as a result of instantiating a template (type). This allow
+ ** gotten an invalid function signature as a result of instantiating a template (type). This allows
  ** us to set up kind of a "trap" for the compiler: we present two overloaded candidate functions
  ** with a different return type; by investigating the resulting return type we're able to figure
  ** out the overload actually picked by the compiler.
diff --git a/src/proc/assetmanager.cpp b/src/proc/assetmanager.cpp
index 8e562dc26..ec7421b4a 100644
--- a/src/proc/assetmanager.cpp
+++ b/src/proc/assetmanager.cpp
@@ -245,11 +245,12 @@ namespace asset {
   template ID<Asset> AssetManager::reg (Asset* obj, const Asset::Ident& idi);
   
   
-  template P<Asset>  AssetManager::getAsset (const ID<Asset>&  id)  throw(lumiera::error::Invalid);
-  template P<Media>  AssetManager::getAsset (const ID<Media>&  id)  throw(lumiera::error::Invalid);
-  template P<Proc>   AssetManager::getAsset (const ID<Proc>&   id)  throw(lumiera::error::Invalid);
-  template P<Struct> AssetManager::getAsset (const ID<Struct>& id)  throw(lumiera::error::Invalid);
-  template P<Meta>   AssetManager::getAsset (const ID<Meta>&   id)  throw(lumiera::error::Invalid);
+  template P<Asset>  AssetManager::getAsset (const ID<Asset>&  id);
+  template P<Media>  AssetManager::getAsset (const ID<Media>&  id);
+  template P<Proc>   AssetManager::getAsset (const ID<Proc>&   id);
+  template P<Struct> AssetManager::getAsset (const ID<Struct>& id);
+  template P<Meta>   AssetManager::getAsset (const ID<Meta>&   id);
+  template P<Pipe>   AssetManager::getAsset (const ID<Pipe>&   id);
   
   template P<Asset>    AssetManager::wrap (const Asset& asset);
   template P<Media>    AssetManager::wrap (const Media& asset);
diff --git a/src/proc/mobject/output-mapping.hpp b/src/proc/mobject/output-mapping.hpp
index 7334d8181..d0495ddc2 100644
--- a/src/proc/mobject/output-mapping.hpp
+++ b/src/proc/mobject/output-mapping.hpp
@@ -33,13 +33,12 @@ namespace mobject {
 
   namespace { // Helper to extract and rebind definition types
     
+    using std::tr1::function;
+    
     template<class DEF>
-    struct _def
+    class _def
       {
-        typedef asset::ID<asset::Pipe>      PId;
-        
-        template<typename RET>
-        RET extractFunctionSignature (RET(DEF::*func)(PId));
+        typedef asset::ID<asset::Pipe> PId;
         
         template<typename FUN>
         struct Rebind;
@@ -50,11 +49,12 @@ namespace mobject {
             typedef RET Res;
           };
         
+        typedef typeof(&DEF::output) OutputMappingMemberFunc;              // GCC extension: "typeof"
+        typedef Rebind<OutputMappingMemberFunc> Rebinder;
         
-        typedef typename Rebind<&DEF::output> Rebinder;
-        
-        typedef typename Rebinder::Res      Res;
-        typedef typename function<Res(PId)> OutputMappingFunc; 
+      public:
+        typedef typename Rebinder::Res Target;
+        typedef function<Target(PId)>  OutputMappingFunc; 
       };
     
   }
@@ -73,7 +73,10 @@ namespace mobject {
   template<class DEF>
   class OutputMapping
     {
+      typedef _def<DEF> Setup;
+      
     public:
+      typedef typename Setup::Target Target;
     };