diff --git a/include/XPath/impl/xpath_arithmetic.hpp b/include/XPath/impl/xpath_arithmetic.hpp
index d55b5bc4..89b2d3a4 100644
--- a/include/XPath/impl/xpath_arithmetic.hpp
+++ b/include/XPath/impl/xpath_arithmetic.hpp
@@ -19,6 +19,8 @@ public:
   PlusOperator(XPathExpression_impl<string_type, string_adaptor>* lhs, XPathExpression_impl<string_type, string_adaptor>* rhs) : 
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const 
   {
@@ -35,6 +37,8 @@ public:
   MinusOperator(XPathExpression_impl<string_type, string_adaptor>* lhs, XPathExpression_impl<string_type, string_adaptor>* rhs) : 
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -51,6 +55,8 @@ public:
   MultiplyOperator(XPathExpression_impl<string_type, string_adaptor>* lhs, XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -67,6 +73,8 @@ public:
   DivideOperator(XPathExpression_impl<string_type, string_adaptor>* lhs, XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -83,6 +91,8 @@ public:
   ModOperator(XPathExpression_impl<string_type, string_adaptor>* lhs, XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -104,6 +114,8 @@ public:
   UnaryNegative(XPathExpression_impl<string_type, string_adaptor>* expr) :
       UnaryExpression<string_type, string_adaptor>(expr) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_expression.hpp b/include/XPath/impl/xpath_expression.hpp
index 7210f5a3..6b04b57f 100644
--- a/include/XPath/impl/xpath_expression.hpp
+++ b/include/XPath/impl/xpath_expression.hpp
@@ -20,6 +20,8 @@ protected:
 public:
   virtual ~XPathExpression_impl() { }
 
+  virtual ValueType type() const = 0;
+
   XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context) const
   {
     ExecutionContext<string_type, string_adaptor> executionContext;
@@ -65,6 +67,8 @@ public:
     return *this;
   } // operator=
 
+  ValueType type() const { return ptr_->type(); }
+
   const XPathExpression_impl<string_type, string_adaptor>* get() const { return ptr_.get(); }
 
   operator bool() const { return ptr_.get(); }
diff --git a/include/XPath/impl/xpath_function.hpp b/include/XPath/impl/xpath_function.hpp
index 005c6291..77d3b4c1 100644
--- a/include/XPath/impl/xpath_function.hpp
+++ b/include/XPath/impl/xpath_function.hpp
@@ -29,6 +29,8 @@ protected:
 public:
   virtual ~XPathFunction() { }
 
+  virtual ValueType type() const = 0;
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const = 0;
 
@@ -85,6 +87,8 @@ class LastFn : public XPathFunction<string_type, string_adaptor>
 public:
   LastFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 0, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -99,6 +103,8 @@ class PositionFn : public XPathFunction<string_type, string_adaptor>
 public:
   PositionFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 0, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -114,6 +120,8 @@ class CountFn : public XPathFunction<string_type, string_adaptor>
 public:
   CountFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -130,6 +138,8 @@ class LocalNameFn : public XPathFunction<string_type, string_adaptor>
 public:
   LocalNameFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -166,6 +176,8 @@ class NamespaceURIFn : public XPathFunction<string_type, string_adaptor>
 public:
   NamespaceURIFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -200,6 +212,8 @@ class NameFn : public XPathFunction<string_type, string_adaptor>
 public:
   NameFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -239,6 +253,8 @@ class StringFn : public XPathFunction<string_type, string_adaptor>
 public:
   StringFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -254,6 +270,8 @@ class ConcatFn : public XPathFunction<string_type, string_adaptor>
 public:
   ConcatFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, -1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -272,6 +290,8 @@ class StartsWithFn : public XPathFunction<string_type, string_adaptor>
 public:
   StartsWithFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, 2, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -300,6 +320,8 @@ class ContainsFn : public XPathFunction<string_type, string_adaptor>
 public:
   ContainsFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, 2, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -316,6 +338,8 @@ class SubstringBeforeFn : public XPathFunction<string_type, string_adaptor>
 public:
   SubstringBeforeFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, 2, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -337,6 +361,8 @@ class SubstringAfterFn : public XPathFunction<string_type, string_adaptor>
 public:
   SubstringAfterFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, 2, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -359,6 +385,8 @@ class SubstringFn : public XPathFunction<string_type, string_adaptor>
 public:
   SubstringFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(2, 3, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -389,6 +417,8 @@ class StringLengthFn : public XPathFunction<string_type, string_adaptor>
 public:
   StringLengthFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -405,6 +435,8 @@ class NormalizeSpaceFn : public XPathFunction<string_type, string_adaptor>
 public:
   NormalizeSpaceFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -422,6 +454,8 @@ class TranslateFn : public XPathFunction<string_type, string_adaptor>
 public:
   TranslateFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(3, 3, args) { }
 
+  virtual ValueType type() const { return STRING; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -456,6 +490,8 @@ class BooleanFn : public XPathFunction<string_type, string_adaptor>
 public:
   BooleanFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -471,6 +507,8 @@ class NotFn : public XPathFunction<string_type, string_adaptor>
 public:
   NotFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -485,6 +523,8 @@ class TrueFn : public XPathFunction<string_type, string_adaptor>
 public:
   TrueFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 0, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -499,6 +539,8 @@ class FalseFn : public XPathFunction<string_type, string_adaptor>
 public:
   FalseFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 0, args) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -519,6 +561,8 @@ class NumberFn : public XPathFunction<string_type, string_adaptor>
 public:
   NumberFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(0, 1, args) { }
   
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -536,6 +580,8 @@ class SumFn : public XPathFunction<string_type, string_adaptor>
 public:
   SumFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -555,6 +601,8 @@ class FloorFn : public XPathFunction<string_type, string_adaptor>
 public:
   FloorFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -570,6 +618,8 @@ class CeilingFn : public XPathFunction<string_type, string_adaptor>
 public:
   CeilingFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -585,6 +635,8 @@ class RoundFn : public XPathFunction<string_type, string_adaptor>
 public:
   RoundFn(const std::vector<XPathExpression<string_type, string_adaptor> >& args) : XPathFunction<string_type, string_adaptor>(1, 1, args) { }
 
+  virtual ValueType type() const { return NUMBER; }
+
   virtual XPathValue_impl<string_type, string_adaptor>* evaluate(const DOM::Node<string_type, string_adaptor>& context,
                                             const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_function_holder.hpp b/include/XPath/impl/xpath_function_holder.hpp
index 317daf5b..45b2131a 100644
--- a/include/XPath/impl/xpath_function_holder.hpp
+++ b/include/XPath/impl/xpath_function_holder.hpp
@@ -29,6 +29,8 @@ public:
     delete func_;
   } // ~FunctionHolder
 
+  virtual ValueType type() const { return func_->type(); }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_logical.hpp b/include/XPath/impl/xpath_logical.hpp
index 345a43d8..b08215a8 100644
--- a/include/XPath/impl/xpath_logical.hpp
+++ b/include/XPath/impl/xpath_logical.hpp
@@ -20,6 +20,8 @@ public:
              XPathExpression_impl<string_type, string_adaptor>* rhs) :
        BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -44,6 +46,8 @@ public:
               XPathExpression_impl<string_type, string_adaptor>* rhs) :
        BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_match.hpp b/include/XPath/impl/xpath_match.hpp
index f42b877a..5aee6390 100644
--- a/include/XPath/impl/xpath_match.hpp
+++ b/include/XPath/impl/xpath_match.hpp
@@ -21,7 +21,7 @@ public:
   MatchExpr& operator=(const MatchExpr& rhs)
   { match_ = rhs.match_; priority_ = rhs.priority_; return *this; }
 
-  double priority() const { return priority_; }
+    double priority() const { return priority_; }
   bool evaluate(const DOM::Node<string_type, string_adaptor>& context,
                 const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -52,6 +52,8 @@ public:
     add_matches(expr);
   } // MatchExpressionWrapper
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context,
 					      const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_relational.hpp b/include/XPath/impl/xpath_relational.hpp
index 537863ca..b03e9290 100644
--- a/include/XPath/impl/xpath_relational.hpp
+++ b/include/XPath/impl/xpath_relational.hpp
@@ -20,6 +20,8 @@ public:
                  XPathExpression_impl<string_type, string_adaptor>* rhs) :
        BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -38,6 +40,8 @@ public:
                     XPathExpression_impl<string_type, string_adaptor>* rhs) :
        BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -56,6 +60,8 @@ public:
                    XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -74,6 +80,8 @@ public:
                          XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -92,6 +100,8 @@ public:
                       XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -110,6 +120,8 @@ public:
                             XPathExpression_impl<string_type, string_adaptor>* rhs) :
       BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return BOOL; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_step.hpp b/include/XPath/impl/xpath_step.hpp
index c3368bca..353c7fba 100644
--- a/include/XPath/impl/xpath_step.hpp
+++ b/include/XPath/impl/xpath_step.hpp
@@ -32,6 +32,8 @@ public:
       delete *p;
   } // ~StepExpression
 
+  virtual ValueType type() const { return NODE_SET; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, const ExecutionContext<string_type, string_adaptor>& executionContext) const = 0;
   virtual XPathValue<string_type, string_adaptor> evaluate(NodeSet<string_type, string_adaptor>& context, const ExecutionContext<string_type, string_adaptor>& executionContext) const = 0;
 
@@ -453,6 +455,8 @@ public:
       delete *i;
   } // ~RelativeLocationPath
 
+  virtual ValueType type() const { return NODE_SET; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
     NodeSet<string_type, string_adaptor> nodes;
diff --git a/include/XPath/impl/xpath_union.hpp b/include/XPath/impl/xpath_union.hpp
index f3951bee..b5bd3ff2 100644
--- a/include/XPath/impl/xpath_union.hpp
+++ b/include/XPath/impl/xpath_union.hpp
@@ -21,6 +21,8 @@ public:
                   XPathExpression_impl<string_type, string_adaptor>* rhs) :
        BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }
 
+  virtual ValueType type() const { return NODE_SET; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XPath/impl/xpath_variable.hpp b/include/XPath/impl/xpath_variable.hpp
index 608afd0a..5227e409 100644
--- a/include/XPath/impl/xpath_variable.hpp
+++ b/include/XPath/impl/xpath_variable.hpp
@@ -21,6 +21,8 @@ public:
   { 
   } // Variable
 
+  virtual ValueType type() const { return ANY; }
+
   virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                               const ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
diff --git a/include/XSLT/impl/xslt_functions.hpp b/include/XSLT/impl/xslt_functions.hpp
index 8d0d2f98..201ffc3d 100644
--- a/include/XSLT/impl/xslt_functions.hpp
+++ b/include/XSLT/impl/xslt_functions.hpp
@@ -18,6 +18,8 @@ public:
   CurrentFunction(const std::vector<Arabica::XPath::XPathExpression<std::string> >& args) :
       Arabica::XPath::XPathFunction<std::string>(0, 0, args) { }
 
+  virtual Arabica::XPath::ValueType type() const { return Arabica::XPath::NODE_SET; }
+
   virtual Arabica::XPath::XPathValue_impl<std::string>* evaluate(const DOM::Node<std::string>& context, 
                                                                  const Arabica::XPath::ExecutionContext<std::string>& executionContext) const
   {
@@ -39,6 +41,8 @@ public:
       baseURI_(currentBase)
   { } 
 
+  virtual Arabica::XPath::ValueType type() const { return Arabica::XPath::NODE_SET; }
+
   virtual Arabica::XPath::XPathValue_impl<std::string>* evaluate(const DOM::Node<std::string>& context,
                                             const Arabica::XPath::ExecutionContext<std::string>& executionContext) const
   {
@@ -84,6 +88,8 @@ public:
   SystemPropertyFunction (const std::vector<Arabica::XPath::XPathExpression<std::string> >& args) :
       Arabica::XPath::XPathFunction<std::string>(1, 1, args) { }
 
+  virtual Arabica::XPath::ValueType type() const { return Arabica::XPath::STRING; }
+
   virtual Arabica::XPath::XPathValue_impl<std::string>* evaluate(const DOM::Node<std::string>& context, 
                                             const Arabica::XPath::ExecutionContext<std::string>& executionContext) const
   {
diff --git a/tests/XPath/execute_test.hpp b/tests/XPath/execute_test.hpp
index 4376e2a6..3633b36f 100644
--- a/tests/XPath/execute_test.hpp
+++ b/tests/XPath/execute_test.hpp
@@ -65,6 +65,8 @@ public:
   TestFunction(const std::vector<Arabica::XPath::XPathExpression<string_type, string_adaptor> >& args) :
       Arabica::XPath::XPathFunction<string_type, string_adaptor>(0, 0, args) { }
 
+  virtual Arabica::XPath::ValueType type() const { return Arabica::XPath::STRING; }
+
   virtual Arabica::XPath::XPathValue_impl<string_type, string_adaptor>* evaluate(const Arabica::DOM::Node<string_type, string_adaptor>& context, 
                                             const Arabica::XPath::ExecutionContext<string_type, string_adaptor>& executionContext) const
   {
@@ -178,6 +180,7 @@ public:
     using namespace Arabica::XPath;
     XPathExpression<string_type, string_adaptor> xpath;
     xpath = parser.compile(SA::construct_from_utf8("root"));
+    assertValuesEqual(NODE_SET, xpath.type());
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);
 
     assertValuesEqual(NODE_SET, result.type());
@@ -190,6 +193,7 @@ public:
   {
     using namespace Arabica::XPath;
     XPathExpression<string_type, string_adaptor> xpath = parser.compile(SA::construct_from_utf8("root/child2"));
+    assertValuesEqual(NODE_SET, xpath.type());
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);
 
     assertValuesEqual(NODE_SET, result.type());
@@ -202,6 +206,7 @@ public:
   {
     using namespace Arabica::XPath;
     XPathExpression<string_type, string_adaptor> xpath = parser.compile(SA::construct_from_utf8("root/*"));
+    assertValuesEqual(NODE_SET, xpath.type());
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);
 
     assertValuesEqual(NODE_SET, result.type());
@@ -215,6 +220,7 @@ public:
   {
     using namespace Arabica::XPath;
     XPathExpression<string_type, string_adaptor> xpath = parser.compile(SA::construct_from_utf8("root/*/text()"));
+    assertValuesEqual(NODE_SET, xpath.type());
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);
 
     assertValuesEqual(NODE_SET, result.type());
@@ -234,6 +240,7 @@ public:
   {
     using namespace Arabica::XPath;
     XPathExpression<string_type, string_adaptor> xpath = parser.compile(SA::construct_from_utf8("*"));
+    assertValuesEqual(NODE_SET, xpath.type());
 
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);
     assertValuesEqual(NODE_SET, result.type());
@@ -283,6 +290,7 @@ public:
     nsContext.addNamespaceDeclaration(SA::construct_from_utf8("urn:something:or:other"), SA::construct_from_utf8("ns"));
     parser.setNamespaceContext(nsContext);
     XPathExpression<string_type, string_adaptor> xpath = parser.compile(SA::construct_from_utf8("/ns:root"));
+    assertValuesEqual(NODE_SET, xpath.type());
     parser.resetNamespaceContext();
 
     XPathValue<string_type, string_adaptor> result = xpath.evaluate(document_);