diff --git a/src/lib/format-util.hpp b/src/lib/format-util.hpp
index 96e539c67..21105d7ca 100644
--- a/src/lib/format-util.hpp
+++ b/src/lib/format-util.hpp
@@ -175,7 +175,7 @@ namespace util {
   inline string
   join (CON&& coll, string const& delim =", ")
   {
-    using Coll = typename lib::meta::Strip<CON>::Type;
+    using Coll = typename lib::meta::Strip<CON>::TypePlain;
     using Val =  typename Coll::value_type;
     
     std::function<string(Val const&)> toString = [] (Val const& val) { return util::toString(val); };
diff --git a/src/lib/meta/trait.hpp b/src/lib/meta/trait.hpp
index 399276768..b92de002a 100644
--- a/src/lib/meta/trait.hpp
+++ b/src/lib/meta/trait.hpp
@@ -182,19 +182,6 @@ namespace meta {
         }
     };
   
-  template<typename X, class B>
-  struct Unwrap<mobject::Placement<X, B> >
-    {
-      typedef X  Type;
-      
-      static X&
-      extract (mobject::Placement<X,B> placement)
-        {
-          ASSERT (placement.isValid());
-          return *placement;
-        }
-    };
-  
   
   /** convenience shortcut: unwrapping free function.
    *  @return reference to the bare element.