diff --git a/include/boost/function_output_iterator.hpp b/include/boost/function_output_iterator.hpp
index 764c118..0e22e03 100644
--- a/include/boost/function_output_iterator.hpp
+++ b/include/boost/function_output_iterator.hpp
@@ -26,7 +26,9 @@ namespace boost {
     typedef void                pointer;
     typedef void                reference;
 
-    explicit function_output_iterator(const UnaryFunction& f = UnaryFunction())
+    explicit function_output_iterator() {}
+
+    explicit function_output_iterator(const UnaryFunction& f)
       : m_f(f) {}
 
     struct output_proxy {