diff --git a/src/lib/diff/diff-message.hpp b/src/lib/diff/diff-message.hpp
index ab3ed204c..59f28a0ac 100644
--- a/src/lib/diff/diff-message.hpp
+++ b/src/lib/diff/diff-message.hpp
@@ -51,6 +51,7 @@
 #include "lib/iter-source.hpp"
 #include "lib/diff/tree-diff.hpp"
 #include "lib/diff/gen-node.hpp"
+#include "lib/meta/util.hpp"
 
 #include <string>
 
@@ -59,6 +60,11 @@ namespace lib {
 namespace diff{
   
   using std::string;
+  using std::__and_;
+  using std::__not_;
+  using lib::meta::enable_if;
+  using lib::meta::can_IterForEach;
+  using lib::meta::can_STL_ForEach;
   
   using DiffStep = TreeDiffLanguage::DiffStep;
   using DiffSource = IterSource<DiffStep>;
@@ -86,6 +92,9 @@ namespace diff{
   struct DiffMessage
     : DiffSource::iterator
     {
+      using _FrontEnd = DiffSource::iterator;
+      
+      
       DiffMessage() = default;
       
       /**
@@ -95,7 +104,12 @@ namespace diff{
        */
       explicit
       DiffMessage(DiffSource* diffGenerationContext)
-        : DiffSource::iterator{DiffSource::build (diffGenerationContext)}
+        : _FrontEnd{DiffSource::build (diffGenerationContext)}
+        { }
+      
+      template<class IT>
+      DiffMessage(IT ii,                      enable_if< can_IterForEach<IT>, void*> =nullptr)
+        : _FrontEnd{iter_source::wrapIter(ii)}
         { }
     };
   
diff --git a/src/lib/iter-adapter.hpp b/src/lib/iter-adapter.hpp
index b41dcae2c..b4d824eb9 100644
--- a/src/lib/iter-adapter.hpp
+++ b/src/lib/iter-adapter.hpp
@@ -249,13 +249,9 @@ namespace lib {
     protected:
       using ConRef = typename iter::TypeBinding<CON>::reference;
       
-      /** allow derived classes to
-       *  access backing container */
-      ConRef
-      source()
-        {
-          return source_;
-        }
+      /** allow derived classes to access backing container */
+      ConRef       source()       { return                source_; }
+      const ConRef source() const { return unConst(this)->source_; }
       
     private:
       void
diff --git a/src/lib/iter-type-binding.hpp b/src/lib/iter-type-binding.hpp
index fa48a0083..7ca5c87e3 100644
--- a/src/lib/iter-type-binding.hpp
+++ b/src/lib/iter-type-binding.hpp
@@ -102,9 +102,9 @@ namespace iter {
   template<typename TY>
   struct TypeBinding<std::shared_ptr<TY>>
     {
-      typedef TY value_type;
-      typedef const TY& reference;
-      typedef const TY* pointer;
+      typedef std::shared_ptr<TY> value_type;
+      typedef std::shared_ptr<TY>& reference;
+      typedef std::shared_ptr<TY>* pointer;
     };