diff --git a/cheatsheet.md b/cheatsheet.md
index 594b2f7..9ff4ad4 100644
--- a/cheatsheet.md
+++ b/cheatsheet.md
@@ -80,6 +80,18 @@ It's not strictly necessary to add types, but it helps with many things. Cloning
 chai.add(chaiscript::user_type<MyClass>, "MyClass");
 ```
 
+## Adding Type Conversions
+
+User defined type conversions are possible, defined in either script or in C++.
+
+A helper function exists for strongly typed and ChaiScript `Vector` function conversion definition:
+
+```
+chai.add(chaiscript::vector_conversion<std::vector<int>>());
+```
+
+This allows you to pass a ChaiScript function to a function requiring `std::vector<int>`
+
 ## Adding Objects
 
 ```
diff --git a/include/chaiscript/chaiscript_threading.hpp b/include/chaiscript/chaiscript_threading.hpp
index 6bac83a..09fc617 100644
--- a/include/chaiscript/chaiscript_threading.hpp
+++ b/include/chaiscript/chaiscript_threading.hpp
@@ -14,8 +14,10 @@
 #include <thread>
 #include <mutex>
 #else
+#ifndef CHAISCRIPT_NO_THREADS_WARNING
 #pragma message ("ChaiScript is compiling without thread safety.")
 #endif
+#endif
 
 #include "chaiscript_defines.hpp"
 
@@ -153,6 +155,7 @@ namespace chaiscript
 
 
           private:
+            /// \todo this leaks thread instances. It needs to be culled from time to time
             std::shared_ptr<T> get_tls() const
             {
               unique_lock<mutex> lock(m_mutex);
diff --git a/include/chaiscript/dispatchkit/bad_boxed_cast.hpp b/include/chaiscript/dispatchkit/bad_boxed_cast.hpp
index 31344d4..c2be40f 100644
--- a/include/chaiscript/dispatchkit/bad_boxed_cast.hpp
+++ b/include/chaiscript/dispatchkit/bad_boxed_cast.hpp
@@ -36,7 +36,7 @@ namespace chaiscript
         }
 
         bad_boxed_cast(Type_Info t_from, const std::type_info &t_to)
-          : from(std::move(t_from)), to(&t_to), m_what("Cannot perform boxed_cast")
+          : from(std::move(t_from)), to(&t_to), m_what("Cannot perform boxed_cast: " + t_from.name() + " to: " + t_to.name())
         {
         }
 
diff --git a/include/chaiscript/dispatchkit/bootstrap_stl.hpp b/include/chaiscript/dispatchkit/bootstrap_stl.hpp
index a763e48..1a03888 100644
--- a/include/chaiscript/dispatchkit/bootstrap_stl.hpp
+++ b/include/chaiscript/dispatchkit/bootstrap_stl.hpp
@@ -319,7 +319,7 @@ namespace chaiscript
       /// Add back insertion sequence concept to the given ContainerType
       /// http://www.sgi.com/tech/stl/BackInsertionSequence.html
       template<typename ContainerType>
-        ModulePtr back_insertion_sequence_type(const std::string &/*type*/, ModulePtr m = std::make_shared<Module>())
+        ModulePtr back_insertion_sequence_type(const std::string &type, ModulePtr m = std::make_shared<Module>())
         {
           typedef typename ContainerType::reference (ContainerType::*backptr)();
 
@@ -328,8 +328,16 @@ namespace chaiscript
 
           typedef void (ContainerType::*push_back)(const typename ContainerType::value_type &);
           m->add(fun(static_cast<push_back>(&ContainerType::push_back)),
-              []()->std::string{
-                if (typeid(typename ContainerType::value_type) == typeid(Boxed_Value)) {
+              [&]()->std::string{
+              if (typeid(typename ContainerType::value_type) == typeid(Boxed_Value)) {
+                m->eval(
+                    "# Pushes the second value onto the container while making a clone of the value\n"
+                    "def push_back(" + type + " container, x)\n"
+                    "{ \n"
+                    "  container.push_back_ref(clone(x)) \n"
+                    "} \n"
+                    );
+
                   return "push_back_ref";
                 } else {
                   return "push_back";
@@ -345,7 +353,7 @@ namespace chaiscript
       /// Front insertion sequence
       /// http://www.sgi.com/tech/stl/FrontInsertionSequence.html
       template<typename ContainerType>
-        ModulePtr front_insertion_sequence_type(const std::string &, ModulePtr m = std::make_shared<Module>())
+        ModulePtr front_insertion_sequence_type(const std::string &type, ModulePtr m = std::make_shared<Module>())
         {
           typedef typename ContainerType::reference (ContainerType::*front_ptr)();
           typedef typename ContainerType::const_reference (ContainerType::*const_front_ptr)() const;
@@ -356,8 +364,15 @@ namespace chaiscript
           m->add(fun(static_cast<const_front_ptr>(&ContainerType::front)), "front");
 
           m->add(fun(static_cast<push_ptr>(&ContainerType::push_front)),
-              []()->std::string{
+              [&]()->std::string{
                 if (typeid(typename ContainerType::value_type) == typeid(Boxed_Value)) {
+                  m->eval(
+                      "# Pushes the second value onto the front of container while making a clone of the value\n"
+                      "def push_front(" + type + " container, x)\n"
+                      "{ \n"
+                      "  container.push_front_ref(clone(x)) \n"
+                      "} \n"
+                      );
                   return "push_front_ref";
                 } else {
                   return "push_front";
diff --git a/include/chaiscript/dispatchkit/boxed_cast.hpp b/include/chaiscript/dispatchkit/boxed_cast.hpp
index 106b9d8..1ddaacc 100644
--- a/include/chaiscript/dispatchkit/boxed_cast.hpp
+++ b/include/chaiscript/dispatchkit/boxed_cast.hpp
@@ -79,13 +79,6 @@ namespace chaiscript
     }
 
 
-#ifdef CHAISCRIPT_MSVC
-    //Thank you MSVC, yes we know that a constant value is being used in the if
-    // statment in THIS VERSION of the template instantiation
-#pragma warning(push)
-#pragma warning(disable : 4127)
-#endif
-
     if (t_conversions && t_conversions->convertable_type<Type>())
     {
       try {
@@ -108,10 +101,6 @@ namespace chaiscript
       throw exception::bad_boxed_cast(bv.get_type_info(), typeid(Type));
     }
 
-#ifdef CHAISCRIPT_MSVC
-#pragma warning(pop)
-#endif
-
   }
 
 }
diff --git a/include/chaiscript/dispatchkit/function_call_detail.hpp b/include/chaiscript/dispatchkit/function_call_detail.hpp
index fb6b5fc..4054b59 100644
--- a/include/chaiscript/dispatchkit/function_call_detail.hpp
+++ b/include/chaiscript/dispatchkit/function_call_detail.hpp
@@ -31,9 +31,9 @@ namespace chaiscript
         struct Function_Caller_Ret
         {
           static Ret call(const std::vector<Const_Proxy_Function> &t_funcs, 
-              const std::vector<Boxed_Value> &params, const Type_Conversions &t_conversions)
+              const std::vector<Boxed_Value> &params, const Type_Conversions *t_conversions)
           {
-            return boxed_cast<Ret>(dispatch::dispatch(t_funcs, params, t_conversions));
+            return boxed_cast<Ret>(dispatch::dispatch(t_funcs, params, t_conversions?*t_conversions:Type_Conversions()), t_conversions);
           }
         };
 
@@ -44,9 +44,9 @@ namespace chaiscript
         struct Function_Caller_Ret<Ret, true>
         {
           static Ret call(const std::vector<Const_Proxy_Function> &t_funcs, 
-              const std::vector<Boxed_Value> &params, const Type_Conversions &t_conversions)
+              const std::vector<Boxed_Value> &params, const Type_Conversions *t_conversions)
           {
-            return Boxed_Number(dispatch::dispatch(t_funcs, params, t_conversions)).get_as<Ret>();
+            return Boxed_Number(dispatch::dispatch(t_funcs, params, t_conversions?*t_conversions:Type_Conversions())).get_as<Ret>();
           }
         };
 
@@ -58,9 +58,9 @@ namespace chaiscript
         struct Function_Caller_Ret<void, false>
         {
           static void call(const std::vector<Const_Proxy_Function> &t_funcs, 
-              const std::vector<Boxed_Value> &params, const Type_Conversions &t_conversions)
+              const std::vector<Boxed_Value> &params, const Type_Conversions *t_conversions)
           {
-            dispatch::dispatch(t_funcs, params, t_conversions);
+            dispatch::dispatch(t_funcs, params, t_conversions?*t_conversions:Type_Conversions());
           }
         };
 
@@ -70,28 +70,49 @@ namespace chaiscript
       template<typename Ret, typename ... Param>
         struct Build_Function_Caller_Helper
         {
-          Build_Function_Caller_Helper(std::vector<Const_Proxy_Function> t_funcs, const Type_Conversions &t_conversions)
+          Build_Function_Caller_Helper(std::vector<Const_Proxy_Function> t_funcs, const Type_Conversions *t_conversions)
             : m_funcs(std::move(t_funcs)),
               m_conversions(t_conversions)
           {
           }
 
-          Ret operator()(Param...param)
+          template<typename ... P>
+          Ret operator()(P&&  ...  param)
           {
             return Function_Caller_Ret<Ret, std::is_arithmetic<Ret>::value && !std::is_same<Ret, bool>::value>::call(m_funcs, { 
-                (std::is_reference<Param>::value&&!(std::is_same<chaiscript::Boxed_Value, typename std::remove_const<typename std::remove_reference<Param>::type>::type>::value))?Boxed_Value(std::ref(param)):Boxed_Value(param)... 
+                box<P>(std::forward<P>(param))...
                 }, m_conversions
 
                 );
 
           }
 
+          template<typename P, typename Q>
+          static auto box(Q&& q) -> typename std::enable_if<std::is_reference<P>::value&&!std::is_same<chaiscript::Boxed_Value, typename std::remove_const<typename std::remove_reference<P>::type>::type>::value, Boxed_Value>::type
+          {
+            return Boxed_Value(std::ref(std::forward<Q>(q)));
+          }
+
+          template<typename P, typename Q>
+          static auto box(Q&& q) -> typename std::enable_if<!std::is_reference<P>::value&&!std::is_same<chaiscript::Boxed_Value, typename std::remove_const<typename std::remove_reference<P>::type>::type>::value, Boxed_Value>::type
+          {
+            return Boxed_Value(std::forward<Q>(q));
+          }
+
+          template<typename P>
+          static Boxed_Value box(Boxed_Value bv)
+          {
+            return bv;
+          }
+
+
           std::vector<Const_Proxy_Function> m_funcs;
-          Type_Conversions m_conversions;
+          const Type_Conversions *m_conversions;
         };
 
 
 
+      /// \todo what happens if t_conversions is deleted out from under us?!
       template<typename Ret, typename ... Params>
         std::function<Ret (Params...)> build_function_caller_helper(Ret (Params...), const std::vector<Const_Proxy_Function> &funcs, const Type_Conversions *t_conversions)
         {
@@ -111,7 +132,7 @@ namespace chaiscript
           }
 */
 
-          return std::function<Ret (Params...)>(Build_Function_Caller_Helper<Ret, Params...>(funcs, t_conversions?*t_conversions:Type_Conversions()));
+          return std::function<Ret (Params...)>(Build_Function_Caller_Helper<Ret, Params...>(funcs, t_conversions));
         }
     }
   }
diff --git a/include/chaiscript/dispatchkit/type_conversions.hpp b/include/chaiscript/dispatchkit/type_conversions.hpp
index 9071df3..602d4d9 100644
--- a/include/chaiscript/dispatchkit/type_conversions.hpp
+++ b/include/chaiscript/dispatchkit/type_conversions.hpp
@@ -337,7 +337,7 @@ namespace chaiscript
       Type_Conversions(const Type_Conversions &t_other)
         : m_mutex(),
           m_conversions(t_other.get_conversions()),
-          m_convertableTypes(),
+          m_convertableTypes(t_other.m_convertableTypes),
           m_num_types(m_conversions.size()),
           m_thread_cache(this),
           m_conversion_saves(this)
@@ -575,6 +575,24 @@ namespace chaiscript
       return chaiscript::make_shared<detail::Type_Conversion_Base, detail::Type_Conversion_Impl<decltype(func)>>(user_type<From>(), user_type<To>(), func);
     }
 
+  template<typename To>
+    Type_Conversion vector_conversion()
+    {
+      auto func = [](const Boxed_Value &t_bv) -> Boxed_Value {
+        const std::vector<Boxed_Value> &from_vec = detail::Cast_Helper<const std::vector<Boxed_Value> &>::cast(t_bv, nullptr);
+
+        To vec;
+
+        for (const Boxed_Value &bv : from_vec) {
+          vec.push_back(detail::Cast_Helper<typename To::value_type>::cast(bv, nullptr));
+        }
+
+        return Boxed_Value(std::move(vec));
+      };
+
+      return chaiscript::make_shared<detail::Type_Conversion_Base, detail::Type_Conversion_Impl<decltype(func)>>(user_type<std::vector<Boxed_Value>>(), user_type<To>(), func);
+    }
+
 }
 
 
diff --git a/include/chaiscript/dispatchkit/type_info.hpp b/include/chaiscript/dispatchkit/type_info.hpp
index e15e508..62dc081 100644
--- a/include/chaiscript/dispatchkit/type_info.hpp
+++ b/include/chaiscript/dispatchkit/type_info.hpp
@@ -136,9 +136,11 @@ namespace chaiscript
 
          static Type_Info get()
         {
-          return Type_Info(std::is_const<typename std::remove_pointer<typename std::remove_reference<T>::type>::type>::value, std::is_reference<T>::value, std::is_pointer<T>::value, 
+          return Type_Info(std::is_const<typename std::remove_pointer<typename std::remove_reference<T>::type>::type>::value, 
+              std::is_reference<T>::value, std::is_pointer<T>::value, 
               std::is_void<T>::value,
-              std::is_arithmetic<T>::value && !std::is_same<typename std::remove_const<T>::type, bool>::value,
+              (std::is_arithmetic<T>::value || std::is_arithmetic<typename std::remove_reference<T>::type>::value)
+                && !std::is_same<typename std::remove_const<T>::type, bool>::value,
               &typeid(T), 
               &typeid(typename Bare_Type<T>::type));
         }
diff --git a/include/chaiscript/language/chaiscript_eval.hpp b/include/chaiscript/language/chaiscript_eval.hpp
index 4295a32..e3b792f 100644
--- a/include/chaiscript/language/chaiscript_eval.hpp
+++ b/include/chaiscript/language/chaiscript_eval.hpp
@@ -1050,7 +1050,12 @@ namespace chaiscript
             std::vector<Boxed_Value> vec;
             if (!children.empty()) {
               for (const auto &child : children[0]->children) {
-                vec.push_back(t_ss->call_function("clone", child->eval(t_ss)));
+                auto obj = child->eval(t_ss);
+                if (!obj.is_return_value()) {
+                  vec.push_back(t_ss->call_function("clone", obj));
+                } else {
+                  vec.push_back(std::move(obj));
+                }
               }
             }
             return const_var(std::move(vec));
@@ -1076,8 +1081,12 @@ namespace chaiscript
             std::map<std::string, Boxed_Value> retval;
 
             for (const auto &child : children[0]->children) {
-              Boxed_Value bv = t_ss->call_function("clone", child->children[1]->eval(t_ss));
-              retval[t_ss->boxed_cast<std::string>(child->children[0]->eval(t_ss))] = std::move(bv);
+              auto obj = child->children[1]->eval(t_ss);
+              if (!obj.is_return_value()) {
+                obj = t_ss->call_function("clone", obj);
+              }
+
+              retval[t_ss->boxed_cast<std::string>(child->children[0]->eval(t_ss))] = std::move(obj);
             }
 
             return const_var(std::move(retval));
diff --git a/include/chaiscript/language/chaiscript_prelude.chai b/include/chaiscript/language/chaiscript_prelude.chai
index 88835c5..0fe2a5a 100644
--- a/include/chaiscript/language/chaiscript_prelude.chai
+++ b/include/chaiscript/language/chaiscript_prelude.chai
@@ -127,18 +127,6 @@ def even(x)
 } 
 
 
-# Pushes the second value onto the container first value while making a clone of the value
-def push_back(container, x) : call_exists(push_back_ref, container, x) 
-{ 
-  container.push_back_ref(clone(x))
-} 
-
-# Pushes the second value onto the front of the container first value while making a clone of the value
-def push_front(container, x) : call_exists(push_front_ref, container, x) 
-{ 
-  container.push_front_ref(clone(x)) 
-} 
-
 # Inserts the third value at the position of the second value into the container of the first
 # while making a clone. 
 def insert_at(container, pos, x) 
diff --git a/src/stl_extra.cpp b/src/stl_extra.cpp
index 6f0c5e4..e391b18 100644
--- a/src/stl_extra.cpp
+++ b/src/stl_extra.cpp
@@ -23,7 +23,11 @@
 
 CHAISCRIPT_MODULE_EXPORT chaiscript::ModulePtr create_chaiscript_module_stl_extra()
 {
-  return chaiscript::bootstrap::standard_library::list_type<std::list<chaiscript::Boxed_Value> >("List");
+
+  auto module = chaiscript::bootstrap::standard_library::list_type<std::list<chaiscript::Boxed_Value> >("List");
+  module->add(chaiscript::bootstrap::standard_library::vector_type<std::vector<uint16_t> >("u16vector"));
+  module->add(chaiscript::vector_conversion<std::vector<uint16_t>>());
+  return module;
 }
 
 #ifdef __llvm__
diff --git a/src/test_module.cpp b/src/test_module.cpp
index c5da4c9..ebccf73 100644
--- a/src/test_module.cpp
+++ b/src/test_module.cpp
@@ -34,6 +34,11 @@ class TestBaseType
     int mdarray[2][3][5];
     std::function<int (int)> func_member;
 
+    void set_string_val(std::string &t_str)
+    {
+      t_str = "42";
+    }
+
   private:
     TestBaseType &operator=(const TestBaseType &) = delete;
 };
@@ -52,6 +57,7 @@ class Type2
       return m_bt.val;
     }
 
+
     const char *get_str() const
     {
       return m_str.c_str();
@@ -171,6 +177,7 @@ CHAISCRIPT_MODULE_EXPORT  chaiscript::ModulePtr create_chaiscript_module_test_mo
   m->add(chaiscript::fun(&TestBaseType::val), "val");
   m->add(chaiscript::fun(&TestBaseType::const_val), "const_val");
   m->add(chaiscript::fun(&TestBaseType::base_only_func), "base_only_func");
+  m->add(chaiscript::fun(&TestBaseType::set_string_val), "set_string_val");
 
 #ifndef CHAISCRIPT_MSVC_12
   // we cannot support these in MSVC_12 because of a bug in the implementation of
diff --git a/unittests/non_const_param.chai b/unittests/non_const_param.chai
new file mode 100644
index 0000000..fa385db
--- /dev/null
+++ b/unittests/non_const_param.chai
@@ -0,0 +1,8 @@
+load_module("test_module")
+
+var t2 = TestBaseType();
+
+var s = "5";
+t2.set_string_val(s);
+assert_equal(s, "42")
+
diff --git a/unittests/vector_push_back.chai b/unittests/vector_push_back.chai
index 82ba4b4..eea34b7 100644
--- a/unittests/vector_push_back.chai
+++ b/unittests/vector_push_back.chai
@@ -3,3 +3,11 @@ x.push_back(3)
 assert_equal(3, x.size())
 assert_equal(3, x.back())
 assert_equal(1, x.front())
+
+
+load_module("stl_extra")
+
+auto uint16v = u16vector();
+uint16v.push_back(1u);
+assert_equal(1, uint16v.front());
+