diff --git a/CMakeLists.txt b/CMakeLists.txt
index 44c8b6d..69aa2d0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -13,7 +13,7 @@ list(APPEND CPACK_SOURCE_IGNORE_FILES ".swp")
 list(APPEND CPACK_SOURCE_IGNORE_FILES ".*~")
 
 set(CPACK_RESOURCE_FILE_LICENSE "${CMAKE_CURRENT_SOURCE_DIR}/license.txt")
-set(CPACK_RESOURCE_FILE_README "${CMAKE_CURRENT_SOURCE_DIR}/readme.txt")
+set(CPACK_RESOURCE_FILE_README "${CMAKE_CURRENT_SOURCE_DIR}/readme.md")
 set(CPACK_PACKAGE_DESCRIPTION_FILE "${CMAKE_CURRENT_SOURCE_DIR}/description.txt")
 
 set(CPACK_PACKAGE_VERSION_MAJOR 4)
diff --git a/include/chaiscript/dispatchkit/bootstrap_stl.hpp b/include/chaiscript/dispatchkit/bootstrap_stl.hpp
index 40f9687..0a53201 100644
--- a/include/chaiscript/dispatchkit/bootstrap_stl.hpp
+++ b/include/chaiscript/dispatchkit/bootstrap_stl.hpp
@@ -176,6 +176,19 @@ namespace chaiscript
             return t_func(t_obj, p1);
 #ifdef BOOST_MSVC
 #pragma warning(pop)
+#endif
+          }
+
+        template<typename T, typename P1>
+          int return_int_impl_non_const(const boost::function<typename T::size_type (T *, P1)> &t_func, T *t_obj, P1 p1)
+          {
+#ifdef BOOST_MSVC
+#pragma warning(push)
+#pragma warning(disable : 4267)
+#endif
+            return t_func(t_obj, p1);
+#ifdef BOOST_MSVC
+#pragma warning(pop)
 #endif
           }
 
@@ -185,6 +198,13 @@ namespace chaiscript
             return boost::bind(&return_int_impl<T, P1>, boost::function<size_t (const T *, P1)>(boost::mem_fn(t_func)), _1, _2);
           }
 
+        template<typename T, typename P1>
+        boost::function<int (T *, P1)> return_int(size_t (T::*t_func)(P1) )
+          {
+            return boost::bind(&return_int_impl_non_const<T, P1>, boost::function<size_t (T*, P1)>(boost::mem_fn(t_func)), _1, _2);
+          }
+
+
         template<typename T, typename P1, typename P2>
           int return_int_impl(const boost::function<typename T::size_type (const T *, P1, P2)> &t_func, const T *t_obj, P1 p1, P2 p2)
           {
@@ -452,6 +472,11 @@ namespace chaiscript
         {
           m->add(fun(boost::function<int (const ContainerType *, const typename ContainerType::key_type &)>(detail::return_int(&ContainerType::count))), "count");
 
+
+          typedef size_t (ContainerType::*erase)(const typename ContainerType::key_type &);
+          erase eraseptr(&ContainerType::erase);
+
+          m->add(fun(boost::function<int (ContainerType *, const typename ContainerType::key_type &)>(detail::return_int(eraseptr))), "erase");
           return m;
         }
 
diff --git a/unittests/map.chai b/unittests/map.chai
index a0a31ee..3fe753a 100644
--- a/unittests/map.chai
+++ b/unittests/map.chai
@@ -1 +1,13 @@
 assert_equal([true, false, true], map([1,2,3], odd))
+
+
+
+var m = ["a":1, "b":2];
+
+assert_equal(1, m.count("a"))
+assert_equal(0, m.count("c"))
+assert_equal(1, m.erase("a"))
+assert_equal(1, m.size())
+assert_equal(0, m.erase("a"))
+
+