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//----------------------------------*-C++-*----------------------------------//
// Copyright 1998 The Regents of the University of California.
// All rights reserved. See LEGAL.LLNL for full text and disclaimer.
//---------------------------------------------------------------------------//

#ifndef __CXX_Objects__h
#define __CXX_Objects__h

// Prevent warnings
#if defined(_XOPEN_SOURCE)
#undef _XOPEN_SOURCE
#endif

#include "Python.h"
#include "Version.hxx"
#include "Config.hxx"
#include "Exception.hxx"


#include <iostream>
#include STR_STREAM
#include <string>
#include <iterator>
#include <utility>
#include <typeinfo>

namespace Py
        {
        typedef int sequence_index_type;        // type of an index into a sequence

        // Forward declarations
        class Object;
        class Type;
        template<TEMPLATE_TYPENAME T> class SeqBase;
        class String;
        class List;
        template<TEMPLATE_TYPENAME T> class MapBase;

        // new_reference_to also overloaded below on Object
        inline PyObject* new_reference_to(PyObject* p)
                {
                Py::_XINCREF(p);
                return p;
                }

        // returning Null() from an extension method triggers a
        // Python exception
        inline PyObject* Null()
                {
                return (static_cast<PyObject*>(0));
                }

        //===========================================================================//
        // class Object
        // The purpose of this class is to serve as the most general kind of
        // Python object, for the purpose of writing C++ extensions in Python
        // Objects hold a PyObject* which they own. This pointer is always a
        // valid pointer to a Python object. In children we must maintain this behavior.
        //
        // Instructions on how to make your own class MyType descended from Object:
        // (0) Pick a base class, either Object or perhaps SeqBase<T> or MapBase<T>.
        //     This example assumes Object.

        // (1) Write a routine int MyType_Check (PyObject *) modeled after PyInt_Check,
        //     PyFloat_Check, etc.

        // (2) Add method accepts:
        //     virtual bool accepts (PyObject *pyob) const {
        //         return pyob && MyType_Check (pyob);
        //     }

        // (3) Include the following constructor and copy constructor
        //
        /*
        explicit MyType (PyObject *pyob): Object(pyob) {
        validate();
        }

        MyType(const Object& other): Object(other.ptr()) {
        validate();
        }
        */

        // Alernate version for the constructor to allow for construction from owned pointers:
        /*
        explicit MyType (PyObject *pyob): Object(pyob) {
        validate();
        }
        */

        // You may wish to add other constructors; see the classes below for examples.
        // Each constructor must use "set" to set the pointer
        // and end by validating the pointer you have created.

        // (4) Each class needs at least these two assignment operators:
        /*
        MyType& operator= (const Object& rhs) {
        return (*this = *rhs);
        }

        Mytype& operator= (PyObject* rhsp) {
        if(ptr() == rhsp) return *this;
        set(rhsp);
        return *this;
        }
        */
        // Note on accepts: constructors call the base class
        // version of a virtual when calling the base class constructor,
        // so the test has to be done explicitly in a descendent.

        // If you are inheriting from PythonExtension<T> to define an object
        // note that it contains PythonExtension<T>::check
        // which you can use in accepts when writing a wrapper class.
        // See Demo/range.h and Demo/range.cxx for an example.

        class Object
                {
        private:
                // the pointer to the Python object
                // Only Object sets this directly.
                // The default constructor for Object sets it to Py_None and
                // child classes must use "set" to set it
                //
                PyObject* p;

        protected:

                void set (PyObject* pyob, bool owned = false)
                        {
                        release();
                        p = pyob;
                        if (!owned)
                                {
                                Py::_XINCREF (p);
                                }
                        validate();
                        }

                void release ()
                        {
                        Py::_XDECREF (p);
                        p = 0;
                        }

                void validate()
                        {
                        // release pointer if not the right type
                        if (! accepts (p))
                                {
                                release ();
                                if(PyErr_Occurred())
                                        { // Error message already set
                                        throw Exception();
                                        }
                                // Better error message if RTTI available
#if defined( _CPPRTTI ) || defined(__GNUG__)
                                std::string s("CXX : Error creating object of type ");
                                s += (typeid (*this)).name();
                                throw TypeError (s);
#else
                                throw TypeError ("CXX: type error.");
#endif
                                }
                        }

        public:
                // Constructor acquires new ownership of pointer unless explicitly told not to.
                explicit Object (PyObject* pyob=Py::_None(), bool owned = false): p (pyob)
                        {
                        if(!owned)
                                {
                                Py::_XINCREF (p);
                                }
                        validate();
                        }

                // Copy constructor acquires new ownership of pointer
                Object (const Object& ob): p(ob.p)
                        {
                        Py::_XINCREF (p);
                        validate();
                        }

                // Assignment acquires new ownership of pointer
                Object& operator= (const Object& rhs)
                        {
                        set(rhs.p);
                        return *this;
                        }

                Object& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }

                // Destructor
                virtual ~Object ()
                        {
                        release ();
                        }

                // Loaning the pointer to others, retain ownership
                PyObject* operator* () const
                        {
                        return p;
                        }

                // Explicit reference_counting changes
                void increment_reference_count()
                        {
                        Py::_XINCREF(p);
                        }

                void decrement_reference_count()
                        {
                        // not allowed to commit suicide, however
                        if(reference_count() == 1)
                        throw RuntimeError("Object::decrement_reference_count error.");
                        Py::_XDECREF(p);
                        }
                // Would like to call this pointer() but messes up STL in SeqBase<T>
                PyObject* ptr () const
                        {
                        return p;
                        }

                //
                // Queries
                //

                // Can pyob be used in this object's constructor?
                virtual bool accepts (PyObject *pyob) const
                        {
                        return (pyob != 0);
                        }

                int reference_count () const
                        { // the reference count
                        return p ? p->ob_refcnt : 0;
                        }

                Type type () const; // the type object associated with this one

                String str () const; // the str() representation

                std::string as_string() const;

                String repr () const; // the repr () representation

                List dir () const; // the dir() list

                bool hasAttr (const std::string& s) const
                        {
                        return PyObject_HasAttrString (p, const_cast<char*>(s.c_str())) ? true: false;
                        }

                Object getAttr (const std::string& s) const
                        {
                        return Object (PyObject_GetAttrString (p, const_cast<char*>(s.c_str())), true);
                        }

                Object getItem (const Object& key) const
                        {
                        return Object (PyObject_GetItem(p, *key), true);
                        }

                long hashValue () const
                        {
                        return PyObject_Hash (p);
                        }

                //
                // int print (FILE* fp, int flags=Py_Print_RAW)
                //      {
                //      return PyObject_Print (p, fp, flags);
                //      }
                //
                bool is(PyObject *pother) const
                        {  // identity test
                        return p == pother;
                        }

                bool is(const Object& other) const
                        { // identity test
                        return p == other.p;
                        }

                bool isCallable () const
                        {
                        return PyCallable_Check (p) != 0;
                        }

                bool isInstance () const
                        {
                        return PyInstance_Check (p) != 0;
                        }

                bool isDict () const
                        {
                        return Py::_Dict_Check (p);
                        }

                bool isList () const
                        {
                        return Py::_List_Check (p);
                        }

                bool isMapping () const
                        {
                        return PyMapping_Check (p) != 0;
                        }

                bool isNumeric () const
                        {
                        return PyNumber_Check (p) != 0;
                        }

                bool isSequence () const
                        {
                        return PySequence_Check (p) != 0;
                        }

                bool isTrue () const
                        {
                        return PyObject_IsTrue (p) != 0;
                        }

                bool isType (const Type& t) const;

                bool isTuple() const
                        {
                        return Py::_Tuple_Check(p);
                        }

                bool isString() const
                        {
                        return Py::_String_Check(p) || Py::_Unicode_Check(p);
                        }

                bool isUnicode() const
                        {
                        return Py::_Unicode_Check(p);
                        }

                // Commands
                void setAttr (const std::string& s, const Object& value)
                        {
                        if(PyObject_SetAttrString (p, const_cast<char*>(s.c_str()), *value) == -1)
                        throw AttributeError ("getAttr failed.");
                        }

                void delAttr (const std::string& s)
                        {
                        if(PyObject_DelAttrString (p, const_cast<char*>(s.c_str())) == -1)
                        throw AttributeError ("delAttr failed.");
                        }

                // PyObject_SetItem is too weird to be using from C++
                // so it is intentionally omitted.

                void delItem (const Object& /*key*/)
                        {
                        //if(PyObject_DelItem(p, *key) == -1)
                        // failed to link on Windows?
                        throw KeyError("delItem failed.");
                        }
                // Equality and comparison use PyObject_Compare

                bool operator==(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k == 0;
                        }

                bool operator!=(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k != 0;

                        }

                bool operator>=(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k >= 0;
                        }

                bool operator<=(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k <= 0;
                        }

                bool operator<(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k < 0;
                        }

                bool operator>(const Object& o2) const
                        {
                        int k = PyObject_Compare (p, *o2);
                        if (PyErr_Occurred()) throw Exception();
                        return k > 0;
                        }
                };
        // End of class Object
        inline PyObject* new_reference_to(const Object& g)
                {
                PyObject* p = g.ptr();
                Py::_XINCREF(p);
                return p;
                }

        // Nothing() is what an extension method returns if
        // there is no other return value.
        inline Object Nothing()
                {
                return Object(Py::_None());
                }

        // Python special None value
        inline Object None()
                {
                return Object(Py::_None());
                }

        // TMM: 31May'01 - Added the #ifndef so I can exlude iostreams.
#ifndef CXX_NO_IOSTREAMS
        std::ostream& operator<< (std::ostream& os, const Object& ob);
#endif

        // Class Type
        class Type: public Object
                {
        public:
                explicit Type (PyObject* pyob, bool owned = false): Object(pyob, owned)
                        {
                        validate();
                        }

                Type (const Object& ob): Object(*ob)
                        {
                        validate();
                        }

                Type(const Type& t): Object(t)
                        {
                        validate();
                        }

                Type& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Type& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Type_Check (pyob);
                        }
                };


        //
        //      Convert an owned Python pointer into a CXX Object
        //
        inline Object asObject (PyObject *p)
                {
                return Object(p, true);
                }




        // ===============================================
        // class Int
        class Int: public Object
                {
        public:
                // Constructor
                explicit Int (PyObject *pyob, bool owned = false): Object (pyob, owned)
                        {
                        validate();
                        }

                Int (const Int& ob): Object(*ob)
                        {
                        validate();
                        }

                // create from long
                explicit Int (long v = 0L): Object(PyInt_FromLong(v), true)
                        {
                        validate();
                        }

                // create from int
                explicit Int (int v)
                        {
                        long w = v;
                        set(PyInt_FromLong(w), true);
                        validate();
                        }

                // create from bool
                explicit Int (bool v)
                        {
                        long w = v ? 1 : 0;
                        set(PyInt_FromLong(w), true);
                        validate();
                        }

                explicit Int (const Object& ob)
                        {
                        set(PyNumber_Int(*ob), true);
                        validate();
                        }

                // Assignment acquires new ownership of pointer

                Int& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Int& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (PyNumber_Int(rhsp), true);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Int_Check (pyob);
                        }
                // convert to long
                operator long() const
                        {
                        return PyInt_AsLong (ptr());
                        }
                // assign from an int
                Int& operator= (int v)
                        {
                        set (PyInt_FromLong (long(v)), true);
                        return *this;
                        }
                // assign from long
                Int& operator= (long v)
                        {
                        set (PyInt_FromLong (v), true);
                        return *this;
                        }
                };

        // ===============================================
        // class Long
        class Long: public Object
                {
        public:
                // Constructor
                explicit Long (PyObject *pyob, bool owned = false): Object (pyob, owned)
                        {
                        validate();
                        }

                Long (const Long& ob): Object(ob.ptr())
                        {
                        validate();
                        }

                // create from long
                explicit Long (long v = 0L)
                        : Object(PyLong_FromLong(v), true)
                        {
                        validate();
                        }
                // create from unsigned long
                explicit Long (unsigned long v)
                        : Object(PyLong_FromUnsignedLong(v), true)
                        {
                        validate();
                        }
                // create from int
                explicit Long (int v)
                        : Object(PyLong_FromLong(static_cast<long>(v)), true)
                        {
                        validate();
                        }

                // try to create from any object
                Long (const Object& ob)
                        : Object(PyNumber_Long(*ob), true)
                        {
                        validate();
                        }

                // Assignment acquires new ownership of pointer

                Long& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Long& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (PyNumber_Long(rhsp), true);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Long_Check (pyob);
                        }
                // convert to long
                operator long() const
                        {
                        return PyLong_AsLong (ptr());
                        }
                // convert to unsigned
                operator unsigned long() const
                        {
                        return PyLong_AsUnsignedLong (ptr());
                        }
                operator double() const
                        {
                        return PyLong_AsDouble (ptr());
                        }
                // assign from an int
                Long& operator= (int v)
                        {
                        set(PyLong_FromLong (long(v)), true);
                        return *this;
                        }
                // assign from long
                Long& operator= (long v)
                        {
                        set(PyLong_FromLong (v), true);
                        return *this;
                        }
                // assign from unsigned long
                Long& operator= (unsigned long v)
                        {
                        set(PyLong_FromUnsignedLong (v), true);
                        return *this;
                        }
                };

        // ===============================================
        // class Float
        //
        class Float: public Object
                {
        public:
                // Constructor
                explicit Float (PyObject *pyob, bool owned = false): Object(pyob, owned)
                        {
                        validate();
                        }

                Float (const Float& f): Object(f)
                        {
                        validate();
                        }

                // make from double
                explicit Float (double v=0.0)
                        : Object(PyFloat_FromDouble (v), true)
                        {
                        validate();
                        }

                // try to make from any object
                Float (const Object& ob)
                        : Object(PyNumber_Float(*ob), true)
                        {
                        validate();
                        }

                Float& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Float& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (PyNumber_Float(rhsp), true);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Float_Check (pyob);
                        }
                // convert to double
                operator double () const
                        {
                        return PyFloat_AsDouble (ptr());
                        }
                // assign from a double
                Float& operator= (double v)
                        {
                        set(PyFloat_FromDouble (v), true);
                        return *this;
                        }
                // assign from an int
                Float& operator= (int v)
                        {
                        set(PyFloat_FromDouble (double(v)), true);
                        return *this;
                        }
                // assign from long
                Float& operator= (long v)
                        {
                        set(PyFloat_FromDouble (double(v)), true);
                        return *this;
                        }
                // assign from an Int
                Float& operator= (const Int& iob)
                        {
                        set(PyFloat_FromDouble (double(long(iob))), true);
                        return *this;
                        }
                };

        // ===============================================
        // class Complex
        class Complex: public Object
                {
        public:
                // Constructor
                explicit Complex (PyObject *pyob, bool owned = false): Object(pyob, owned)
                        {
                        validate();
                        }

                Complex (const Complex& f): Object(f)
                        {
                        validate();
                        }

                // make from double
                explicit Complex (double v=0.0, double w=0.0)
                        :Object(PyComplex_FromDoubles (v, w), true)
                        {
                        validate();
                        }

                Complex& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Complex& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Complex_Check (pyob);
                        }
                // convert to Py_complex
                operator Py_complex () const
                        {
                        return PyComplex_AsCComplex (ptr());
                        }
                // assign from a Py_complex
                Complex& operator= (const Py_complex& v)
                        {
                        set(PyComplex_FromCComplex (v), true);
                        return *this;
                        }
                // assign from a double
                Complex& operator= (double v)
                        {
                        set(PyComplex_FromDoubles (v, 0.0), true);
                        return *this;
                        }
                // assign from an int
                Complex& operator= (int v)
                        {
                        set(PyComplex_FromDoubles (double(v), 0.0), true);
                        return *this;
                        }
                // assign from long
                Complex& operator= (long v)
                        {
                        set(PyComplex_FromDoubles (double(v), 0.0), true);
                        return *this;
                        }
                // assign from an Int
                Complex& operator= (const Int& iob)
                        {
                        set(PyComplex_FromDoubles (double(long(iob)), 0.0), true);
                        return *this;
                        }

                double real() const
                        {
                        return PyComplex_RealAsDouble(ptr());
                        }

                double imag() const
                        {
                        return PyComplex_ImagAsDouble(ptr());
                        }
                };
        // Sequences
        // Sequences are here represented as sequences of items of type T.
        // The base class SeqBase<T> represents that.
        // In basic Python T is always "Object".

        // seqref<T> is what you get if you get elements from a non-const SeqBase<T>.
        // Note: seqref<T> could probably be a nested class in SeqBase<T> but that might stress
        // some compilers needlessly. Simlarly for mapref later.

        // While this class is not intended for enduser use, it needs some public
        // constructors for the benefit of the STL.

        // See Scott Meyer's More Essential C++ for a description of proxies.
        // This application is even more complicated. We are doing an unusual thing
        // in having a double proxy. If we want the STL to work
        // properly we have to compromise by storing the rvalue inside. The
        // entire Object API is repeated so that things like s[i].isList() will
        // work properly.

        // Still, once in a while a weird compiler message may occur using expressions like x[i]
        // Changing them to Object(x[i]) helps the compiler to understand that the
        // conversion of a seqref to an Object is wanted.

        template<TEMPLATE_TYPENAME T>
        class seqref
                {
        protected:
                SeqBase<T>& s; // the sequence
                int offset; // item number
                T the_item; // lvalue
        public:

                seqref (SeqBase<T>& seq, sequence_index_type j)
                        : s(seq), offset(j), the_item (s.getItem(j))
                        {}

                seqref (const seqref<T>& range)
                        : s(range.s), offset(range.offset), the_item(range.the_item)
                        {}

                // TMM: added this seqref ctor for use with STL algorithms
                seqref (Object& obj)
                        : s(dynamic_cast< SeqBase<T>&>(obj))
                        , offset( NULL )
                        , the_item(s.getItem(offset))
                        {}
                ~seqref()
                        {}

                operator T() const
                        { // rvalue
                        return the_item;
                        }

                seqref<T>& operator=(const seqref<T>& rhs)
                        { //used as lvalue
                        the_item = rhs.the_item;
                        s.setItem(offset, the_item);
                        return *this;
                        }

                seqref<T>& operator=(const T& ob)
                        { // used as lvalue
                        the_item = ob;
                        s.setItem(offset, ob);
                        return *this;
                        }

                // forward everything else to the item
                PyObject* ptr () const
                        {
                        return the_item.ptr();
                        }

                int reference_count () const
                        { // the reference count
                        return the_item.reference_count();
                        }

                Type type () const
                        {
                        return the_item.type();
                        }

                String str () const;

                String repr () const;

                bool hasAttr (const std::string& attr_name) const
                        {
                        return the_item.hasAttr(attr_name);
                        }

                Object getAttr (const std::string& attr_name) const
                        {
                        return the_item.getAttr(attr_name);
                        }

                Object getItem (const Object& key) const
                        {
                        return the_item.getItem(key);
                        }

                long hashValue () const
                        {
                        return the_item.hashValue();
                        }

                bool isCallable () const
                        {
                        return the_item.isCallable();
                        }

                bool isDict () const
                        {
                        return the_item.isDict();
                        }

                bool isList () const
                        {
                        return the_item.isList();
                        }

                bool isMapping () const
                        {
                        return the_item.isMapping();
                        }

                bool isNumeric () const
                        {
                        return the_item.isNumeric();
                        }

                bool isSequence () const
                        {
                        return the_item.isSequence();
                        }

                bool isTrue () const
                        {
                        return the_item.isTrue();
                        }

                bool isType (const Type& t) const
                        {
                        return the_item.isType (t);
                        }

                bool isTuple() const
                        {
                        return the_item.isTuple();
                        }

                bool isString() const
                        {
                        return the_item.isString();
                        }
                // Commands
                void setAttr (const std::string& attr_name, const Object& value)
                        {
                        the_item.setAttr(attr_name, value);
                        }

                void delAttr (const std::string& attr_name)
                        {
                        the_item.delAttr(attr_name);
                        }

                void delItem (const Object& key)
                        {
                        the_item.delItem(key);
                        }

                bool operator==(const Object& o2) const
                        {
                        return the_item == o2;
                        }

                bool operator!=(const Object& o2) const
                        {
                        return the_item != o2;
                        }

                bool operator>=(const Object& o2) const
                        {
                        return the_item >= o2;
                        }

                bool operator<=(const Object& o2) const
                        {
                        return the_item <= o2;
                        }

                bool operator<(const Object& o2) const
                        {
                        return the_item < o2;
                        }

                bool operator>(const Object& o2) const
                        {
                        return the_item > o2;
                        }
                }; // end of seqref


        // class SeqBase<T>
        // ...the base class for all sequence types

        template<TEMPLATE_TYPENAME T>
        class SeqBase: public Object
                {
        public:
                // STL definitions
                typedef size_t size_type;
                typedef seqref<T> reference;
                typedef T const_reference;
                typedef seqref<T>* pointer;
                typedef int difference_type;
                typedef T value_type;           // TMM: 26Jun'01

                virtual size_type max_size() const
                        {
                        return std::string::npos; // ?
                        }

                virtual size_type capacity() const
                        {
                        return size();
                        }

                virtual void swap(SeqBase<T>& c)
                        {
                        SeqBase<T> temp = c;
                        c = ptr();
                        set(temp.ptr());
                        }

                virtual size_type size () const
                        {
                        return PySequence_Length (ptr());
                        }

                explicit SeqBase<T> ()
                        :Object(PyTuple_New(0), true)
                        {
                        validate();
                        }

                explicit SeqBase<T> (PyObject* pyob, bool owned=false)
                        : Object(pyob, owned)
                        {
                        validate();
                        }

                SeqBase<T> (const Object& ob): Object(ob)
                        {
                        validate();
                        }

                // Assignment acquires new ownership of pointer

                SeqBase<T>& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                SeqBase<T>& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }

                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && PySequence_Check (pyob);
                        }

                size_type length () const
                        {
                        return PySequence_Length (ptr());
                        }

                // Element access
                const T operator[](sequence_index_type index) const
                        {
                        return getItem(index);
                        }

                seqref<T> operator[](sequence_index_type index)
                        {
                        return seqref<T>(*this, index);
                        }

                virtual T getItem (sequence_index_type i) const
                        {
                        return T(asObject(PySequence_GetItem (ptr(), i)));
                        }

                virtual void setItem (sequence_index_type i, const T& ob)
                        {
                        if (PySequence_SetItem (ptr(), i, *ob) == -1)
                                {
                                throw Exception();
                                }
                        }

                SeqBase<T> repeat (int count) const
                        {
                        return SeqBase<T> (PySequence_Repeat (ptr(), count), true);
                        }

                SeqBase<T> concat (const SeqBase<T>& other) const
                        {
                        return SeqBase<T> (PySequence_Concat(ptr(), *other), true);
                        }

                // more STL compatability
                const T front () const
                        {
                        return getItem(0);
                        }

                seqref<T> front()
                        {
                        return seqref<T>(this, 0);
                        }

                const T back () const
                        {
                        return getItem(size()-1);
                        }

                seqref<T> back()
                        {
                        return seqref<T>(this, size()-1);
                        }

                void verify_length(size_type required_size) const
                        {
                        if (size() != required_size)
                        throw IndexError ("Unexpected SeqBase<T> length.");
                        }

                void verify_length(size_type min_size, size_type max_size) const
                        {
                        size_type n = size();
                        if (n < min_size || n > max_size)
                        throw IndexError ("Unexpected SeqBase<T> length.");
                        }

                class iterator
                        : public random_access_iterator_parent(seqref<T>)
                        {
                protected:
                        friend class SeqBase<T>;
                        SeqBase<T>* seq;
                        int count;

                public:
                        ~iterator ()
                                {}

                        iterator ()
                                : seq( 0 )
                                , count( 0 )
                                {}

                        iterator (SeqBase<T>* s, int where)
                                : seq( s )
                                , count( where )
                                {}

                        iterator (const iterator& other)
                                : seq( other.seq )
                                , count( other.count )
                                {}

                        bool eql (const iterator& other) const
                                {
                                return (*seq == *other.seq) && (count == other.count);
                                }

                        bool neq (const iterator& other) const
                                {
                                return (*seq != *other.seq) || (count != other.count);
                                }

                        bool lss (const iterator& other) const
                                {
                                return (count < other.count);
                                }

                        bool gtr (const iterator& other) const
                                {
                                return (count > other.count);
                                }

                        bool leq (const iterator& other) const
                                {
                                return (count <= other.count);
                                }

                        bool geq (const iterator& other) const
                                {
                                return (count >= other.count);
                                }

                        seqref<T> operator*()
                                {
                                return seqref<T>(*seq, count);
                                }

                        seqref<T> operator[] (sequence_index_type i)
                                {
                                return seqref<T>(*seq, count + i);
                                }

                        iterator& operator=(const iterator& other)
                                {
                                if (this == &other) return *this;
                                seq = other.seq;
                                count = other.count;
                                return *this;
                                }

                        iterator operator+(int n) const
                                {
                                return iterator(seq, count + n);
                                }

                        iterator operator-(int n) const
                                {
                                return iterator(seq, count - n);
                                }

                        iterator& operator+=(int n)
                                {
                                count = count + n;
                                return *this;
                                }

                        iterator& operator-=(int n)
                                {
                                count = count - n;
                                return *this;
                                }

                        int operator-(const iterator& other) const
                                {
                                if (*seq != *other.seq)
                                throw RuntimeError ("SeqBase<T>::iterator comparison error");
                                return count - other.count;
                                }

                        // prefix ++
                        iterator& operator++ ()
                                { count++; return *this;}
                        // postfix ++
                        iterator operator++ (int)
                                { return iterator(seq, count++);}
                        // prefix --
                        iterator& operator-- ()
                                { count--; return *this;}
                        // postfix --
                        iterator operator-- (int)
                                { return iterator(seq, count--);}

                        std::string diagnose() const
                                {
                                std::OSTRSTREAM oss;
                                oss << "iterator diagnosis " << seq << ", " << count << std::ends;
                                return std::string(oss.str());
                                }
                        };    // end of class SeqBase<T>::iterator

                iterator begin ()
                        {
                        return iterator(this, 0);
                        }

                iterator end ()
                        {
                        return iterator(this, length());
                        }

                class const_iterator
                        : public random_access_iterator_parent(const Object)
                        {
                protected:
                        friend class SeqBase<T>;
                        const SeqBase<T>* seq;
                        sequence_index_type count;

                public:
                        ~const_iterator ()
                                {}

                        const_iterator ()
                                : seq( 0 )
                                , count( 0 )
                                {}

                        const_iterator (const SeqBase<T>* s, int where)
                                : seq( s )
                                , count( where )
                                {}

                        const_iterator(const const_iterator& other)
                                : seq( other.seq )
                                , count( other.count )
                                {}

                        const T operator*() const
                                {
                                return seq->getItem(count);
                                }

                        const T operator[] (sequence_index_type i) const
                                {
                                return seq->getItem(count + i);
                                }

                        const_iterator& operator=(const const_iterator& other)
                                {
                                if (this == &other) return *this;
                                seq = other.seq;
                                count = other.count;
                                return *this;
                                }

                        const_iterator operator+(int n) const
                                {
                                return const_iterator(seq, count + n);
                                }

                        bool eql (const const_iterator& other) const
                                {
                                return (*seq == *other.seq) && (count == other.count);
                                }

                        bool neq (const const_iterator& other) const
                                {
                                return (*seq != *other.seq) || (count != other.count);
                                }

                        bool lss (const const_iterator& other) const
                                {
                                return (count < other.count);
                                }

                        bool gtr (const const_iterator& other) const
                                {
                                return (count > other.count);
                                }

                        bool leq (const const_iterator& other) const
                                {
                                return (count <= other.count);
                                }

                        bool geq (const const_iterator& other) const
                                {
                                return (count >= other.count);
                                }

                        const_iterator operator-(int n)
                                {
                                return const_iterator(seq, count - n);
                                }

                        const_iterator& operator+=(int n)
                                {
                                count = count + n;
                                return *this;
                                }

                        const_iterator& operator-=(int n)
                                {
                                count = count - n;
                                return *this;
                                }

                        int operator-(const const_iterator& other) const
                                {
                                if (*seq != *other.seq)
                                throw RuntimeError ("SeqBase<T>::const_iterator::- error");
                                return count - other.count;
                                }
                        // prefix ++
                        const_iterator& operator++ ()
                                { count++; return *this;}
                        // postfix ++
                        const_iterator operator++ (int)
                                { return const_iterator(seq, count++);}
                        // prefix --
                        const_iterator& operator-- ()
                                { count--; return *this;}
                        // postfix --
                        const_iterator operator-- (int)
                                { return const_iterator(seq, count--);}
                        };    // end of class SeqBase<T>::const_iterator

                const_iterator begin () const
                        {
                        return const_iterator(this, 0);
                        }

                const_iterator end () const
                        {
                        return const_iterator(this, length());
                        }
                };

        // Here's an important typedef you might miss if reading too fast...
        typedef SeqBase<Object> Sequence;

        template <TEMPLATE_TYPENAME T> bool operator==(const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator!=(const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator< (const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator> (const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator<=(const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator>=(const EXPLICIT_TYPENAME SeqBase<T>::iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::iterator& right);

        template <TEMPLATE_TYPENAME T> bool operator==(const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator!=(const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator< (const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator> (const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator<=(const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator>=(const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& left, const EXPLICIT_TYPENAME SeqBase<T>::const_iterator& right); 


        extern bool operator==(const Sequence::iterator& left, const Sequence::iterator& right);
        extern bool operator!=(const Sequence::iterator& left, const Sequence::iterator& right);
        extern bool operator< (const Sequence::iterator& left, const Sequence::iterator& right);
        extern bool operator> (const Sequence::iterator& left, const Sequence::iterator& right);
        extern bool operator<=(const Sequence::iterator& left, const Sequence::iterator& right);
        extern bool operator>=(const Sequence::iterator& left, const Sequence::iterator& right);

        extern bool operator==(const Sequence::const_iterator& left, const Sequence::const_iterator& right);
        extern bool operator!=(const Sequence::const_iterator& left, const Sequence::const_iterator& right);
        extern bool operator< (const Sequence::const_iterator& left, const Sequence::const_iterator& right);
        extern bool operator> (const Sequence::const_iterator& left, const Sequence::const_iterator& right);
        extern bool operator<=(const Sequence::const_iterator& left, const Sequence::const_iterator& right);
        extern bool operator>=(const Sequence::const_iterator& left, const Sequence::const_iterator& right); 

        // ==================================================
        // class Char
        // Python strings return strings as individual elements.
        // I'll try having a class Char which is a String of length 1
        //
        typedef std::basic_string<Py_UNICODE> unicodestring;
        extern Py_UNICODE unicode_null_string[1];

        class Char: public Object
                {
        public:
                explicit Char (PyObject *pyob, bool owned = false): Object(pyob, owned)
                        {
                        validate();
                        }

                Char (const Object& ob): Object(ob)
                        {
                        validate();
                        }

                Char (const std::string& v = "")
                        :Object(PyString_FromStringAndSize (const_cast<char*>(v.c_str()),1), true)
                        {
                        validate();
                        }

                Char (char v)
                        : Object(PyString_FromStringAndSize (&v, 1), true)
                        {
                        validate();
                        }

                Char (Py_UNICODE v)
                        : Object(PyUnicode_FromUnicode (&v, 1), true)
                        {
                        validate();
                        }
                // Assignment acquires new ownership of pointer
                Char& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Char& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }

                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && (Py::_String_Check(pyob) || Py::_Unicode_Check(pyob)) && PySequence_Length (pyob) == 1;
                        }

                // Assignment from C string
                Char& operator= (const std::string& v)
                        {
                        set(PyString_FromStringAndSize (const_cast<char*>(v.c_str()),1), true);
                        return *this;
                        }

                Char& operator= (char v)
                        {
                        set(PyString_FromStringAndSize (&v, 1), true);
                        return *this;
                        }

                Char& operator= (const unicodestring& v)
                        {
                        set(PyUnicode_FromUnicode (const_cast<Py_UNICODE*>(v.data()),1), true);
                        return *this;
                        }

                Char& operator= (Py_UNICODE v)
                        {
                        set(PyUnicode_FromUnicode (&v, 1), true);
                        return *this;
                        }

                // Conversion
                operator String() const;

                operator std::string () const
                        {
                        return std::string(PyString_AsString (ptr()));
                        }
                };

        class String: public SeqBase<Char>
                {
        public:
                virtual size_type capacity() const
                        {
                        return max_size();
                        }

                explicit String (PyObject *pyob, bool owned = false): SeqBase<Char>(pyob, owned)
                        {
                        validate();
                        }

                String (const Object& ob): SeqBase<Char>(ob)
                        {
                        validate();
                        }

                String()
                        : SeqBase<Char>( PyString_FromStringAndSize( "", 0 ), true )
                        {
                        validate();
                        }

                String( const std::string& v )
                        : SeqBase<Char>( PyString_FromStringAndSize( const_cast<char*>(v.data()),
                                static_cast<int>( v.length() ) ), true )
                        {
                        validate();
                        }

                String( const char *s, const char *encoding, const char *error="strict" )
                        : SeqBase<Char>( PyUnicode_Decode( s, strlen( s ), encoding, error ), true )
                        {
                        validate();
                        }

                String( const char *s, int len, const char *encoding, const char *error="strict" )
                        : SeqBase<Char>( PyUnicode_Decode( s, len, encoding, error ), true )
                        {
                        validate();
                        }

                String( const std::string &s, const char *encoding, const char *error="strict" )
                        : SeqBase<Char>( PyUnicode_Decode( s.c_str(), s.length(), encoding, error ), true )
                        {
                        validate();
                        }

                String( const std::string& v, std::string::size_type vsize )
                        : SeqBase<Char>(PyString_FromStringAndSize( const_cast<char*>(v.data()),
                                        static_cast<int>( vsize ) ), true)
                        {
                        validate();
                        }

                String( const char *v, int vsize )
                        : SeqBase<Char>(PyString_FromStringAndSize( const_cast<char*>(v), vsize ), true )
                        {
                        validate();
                        }

                String( const char* v )
                        : SeqBase<Char>( PyString_FromString( v ), true )
                        {
                        validate();
                        }

                // Assignment acquires new ownership of pointer
                String& operator= ( const Object& rhs )
                        {
                        return *this = *rhs;
                        }

                String& operator= (PyObject* rhsp)
                        {
                        if( ptr() == rhsp )
                                return *this;
                        set (rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && (Py::_String_Check(pyob) || Py::_Unicode_Check(pyob));
                        }

                // Assignment from C string
                String& operator= (const std::string& v)
                        {
                        set( PyString_FromStringAndSize( const_cast<char*>( v.data() ),
                                        static_cast<int>( v.length() ) ), true );
                        return *this;
                        }
                String& operator= (const unicodestring& v)
                        {
                        set( PyUnicode_FromUnicode( const_cast<Py_UNICODE*>( v.data() ),
                                        static_cast<int>( v.length() ) ), true );
                        return *this;
                        }


                // Encode
                String encode( const char *encoding, const char *error="strict" )
                        {
                        if( isUnicode() )
                        {
                                return String( PyUnicode_AsEncodedString( ptr(), encoding, error ) );
                        }
                        else
                        {
                                return String( PyString_AsEncodedObject( ptr(), encoding, error ) );
                        }
                        }

                String decode( const char *encoding, const char *error="strict" )
                        {
                        return Object( PyString_AsDecodedObject( ptr(), encoding, error ) );
                        }

                // Queries
                virtual size_type size () const
                        {
                        if( isUnicode() )
                        {
                                return static_cast<size_type>( PyUnicode_GET_SIZE (ptr()) );
                        }
                        else
                        {
                                return static_cast<size_type>( PyString_Size (ptr()) );
                        }
                        }

                operator std::string () const
                        {
                        return as_std_string();
                        }

                std::string as_std_string() const
                        {
                        if( isUnicode() )
                        {
                                throw TypeError("cannot return std::string from Unicode object");
                        }
                        else
                        {
                                return std::string( PyString_AsString( ptr() ), static_cast<size_type>( PyString_Size( ptr() ) ) );
                        }
                        }

                unicodestring as_unicodestring() const
                        {
                        if( isUnicode() )
                        {
                                return unicodestring( PyUnicode_AS_UNICODE( ptr() ),
                                        static_cast<size_type>( PyUnicode_GET_SIZE( ptr() ) ) );
                        }
                        else
                        {
                                throw TypeError("can only return unicodestring from Unicode object");
                        }
                        }
                };

        // ==================================================
        // class Tuple
        class Tuple: public Sequence
                {
        public:
                virtual void setItem (sequence_index_type offset, const Object&ob)
                        {
                        // note PyTuple_SetItem is a thief...
                        if(PyTuple_SetItem (ptr(), offset, new_reference_to(ob)) == -1)
                                {
                                throw Exception();
                                }
                        }

                // Constructor
                explicit Tuple (PyObject *pyob, bool owned = false): Sequence (pyob, owned)
                        {
                        validate();
                        }

                Tuple (const Object& ob): Sequence(ob)
                        {
                        validate();
                        }

                // New tuple of a given size
                explicit Tuple (int size = 0)
                        {
                        set(PyTuple_New (size), true);
                        validate ();
                        for (sequence_index_type i=0; i < size; i++)
                                {
                                if(PyTuple_SetItem (ptr(), i, new_reference_to(Py::_None())) == -1)
                                        {
                                        throw Exception();
                                        }
                                }
                        }
                // Tuple from any sequence
                explicit Tuple (const Sequence& s)
                        {
                        sequence_index_type limit( sequence_index_type( s.length() ) );

                        set(PyTuple_New (limit), true);
                        validate();
                        
                        for(sequence_index_type i=0; i < limit; i++)
                                {
                                if(PyTuple_SetItem (ptr(), i, new_reference_to(s[i])) == -1)
                                        {
                                        throw Exception();
                                        }
                                }
                        }
                // Assignment acquires new ownership of pointer

                Tuple& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Tuple& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Tuple_Check (pyob);
                        }

                Tuple getSlice (int i, int j) const
                        {
                        return Tuple (PySequence_GetSlice (ptr(), i, j), true);
                        }

                };

        // ==================================================
        // class List

        class List: public Sequence
                {
        public:
                // Constructor
                explicit List (PyObject *pyob, bool owned = false): Sequence(pyob, owned)
                        {
                        validate();
                        }
                List (const Object& ob): Sequence(ob)
                        {
                        validate();
                        }
                // Creation at a fixed size
                List (int size = 0)
                        {
                        set(PyList_New (size), true);
                        validate();
                        for (sequence_index_type i=0; i < size; i++)
                                {
                                if(PyList_SetItem (ptr(), i, new_reference_to(Py::_None())) == -1)
                                        {
                                        throw Exception();
                                        }
                                }
                        }

                // List from a sequence
                List (const Sequence& s): Sequence()
                        {
                        int n = s.length();
                        set(PyList_New (n), true);
                        validate();
                        for (sequence_index_type i=0; i < n; i++)
                                {
                                if(PyList_SetItem (ptr(), i, new_reference_to(s[i])) == -1)
                                        {
                                        throw Exception();
                                        }
                                }
                        }

                virtual size_type capacity() const
                        {
                        return max_size();
                        }
                // Assignment acquires new ownership of pointer

                List& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                List& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_List_Check (pyob);
                        }

                List getSlice (int i, int j) const
                        {
                        return List (PyList_GetSlice (ptr(), i, j), true);
                        }

                void setSlice (int i, int j, const Object& v)
                        {
                        if(PyList_SetSlice (ptr(), i, j, *v) == -1)
                                {
                                throw Exception();
                                }
                        }

                void append (const Object& ob)
                        {
                        if(PyList_Append (ptr(), *ob) == -1)
                                {
                                throw Exception();
                                }
                        }

                void insert (int i, const Object& ob)
                        {
                        if(PyList_Insert (ptr(), i, *ob) == -1)
                                {
                                throw Exception();
                                }
                        }

                void sort ()
                        {
                        if(PyList_Sort(ptr()) == -1)
                                {
                                throw Exception();
                                }
                        }

                void reverse ()
                        {
                        if(PyList_Reverse(ptr()) == -1)
                                {
                                throw Exception();
                                }
                        }
                };


        // Mappings
        // ==================================================
        template<TEMPLATE_TYPENAME T>
        class mapref
                {
        protected:
                MapBase<T>& s; // the map
                Object key; // item key
                T the_item;

        public:
                mapref<T> (MapBase<T>& map, const std::string& k)
                        : s(map), the_item()
                        {
                        key = String(k);
                        if(map.hasKey(key)) the_item = map.getItem(key);
                        };

                mapref<T> (MapBase<T>& map, const Object& k)
                        : s(map), key(k), the_item()
                        {
                        if(map.hasKey(key)) the_item = map.getItem(key);
                        };

/*
                ~mapref<T>()
                        {}
*/

                // MapBase<T> stuff
                // lvalue
                mapref<T>& operator=(const mapref<T>& other)
                        {
                        if(this == &other) return *this;
                        the_item = other.the_item;
                        s.setItem(key, other.the_item);
                        return *this;
                        };

                mapref<T>& operator= (const T& ob)
                        {
                        the_item = ob;
                        s.setItem (key, ob);
                        return *this;
                        }

                // rvalue
                operator T() const
                        {
                        return the_item;
                        }

                // forward everything else to the_item
                PyObject* ptr () const
                        {
                        return the_item.ptr();
                        }

                int reference_count () const
                        { // the mapref count
                        return the_item.reference_count();
                        }

                Type type () const
                        {
                        return the_item.type();
                        }

                String str () const
                        {
                        return the_item.str();
                        }

                String repr () const
                        {
                        return the_item.repr();
                        }

                bool hasAttr (const std::string& attr_name) const
                        {
                        return the_item.hasAttr(attr_name);
                        }

                Object getAttr (const std::string& attr_name) const
                        {
                        return the_item.getAttr(attr_name);
                        }

                Object getItem (const Object& k) const
                        {
                        return the_item.getItem(k);
                        }

                long hashValue () const
                        {
                        return the_item.hashValue();
                        }

                bool isCallable () const
                        {
                        return the_item.isCallable();
                        }

                bool isList () const
                        {
                        return the_item.isList();
                        }

                bool isMapping () const
                        {
                        return the_item.isMapping();
                        }

                bool isNumeric () const
                        {
                        return the_item.isNumeric();
                        }

                bool isSequence () const
                        {
                        return the_item.isSequence();
                        }

                bool isTrue () const
                        {
                        return the_item.isTrue();
                        }

                bool isType (const Type& t) const
                        {
                        return the_item.isType (t);
                        }

                bool isTuple() const
                        {
                        return the_item.isTuple();
                        }

                bool isString() const
                        {
                        return the_item.isString();
                        }

                // Commands
                void setAttr (const std::string& attr_name, const Object& value)
                        {
                        the_item.setAttr(attr_name, value);
                        }

                void delAttr (const std::string& attr_name)
                        {
                        the_item.delAttr(attr_name);
                        }

                void delItem (const Object& k)
                        {
                        the_item.delItem(k);
                        }
                }; // end of mapref

        // TMM: now for mapref<T>
        template< class T >
        bool operator==(const mapref<T>& left, const mapref<T>& right)
                {
                return true;    // NOT completed.
                }

        template< class T >
        bool operator!=(const mapref<T>& left, const mapref<T>& right)
                {
                return true;    // not completed.
                }

        template<TEMPLATE_TYPENAME T>
        class MapBase: public Object
                {
        protected:
                explicit MapBase<T>()
                        {}
        public:
                // reference: proxy class for implementing []
                // TMM: 26Jun'01 - the types
                // If you assume that Python mapping is a hash_map...
                // hash_map::value_type is not assignable, but
                // (*it).second = data must be a valid expression
                typedef size_t size_type;
                typedef Object key_type;
                typedef mapref<T> data_type;
                typedef std::pair< const T, T > value_type;
                typedef std::pair< const T, mapref<T> > reference;
                typedef const std::pair< const T, const T > const_reference;
                typedef std::pair< const T, mapref<T> > pointer;

                // Constructor
                explicit MapBase<T> (PyObject *pyob, bool owned = false): Object(pyob, owned)
                        {
                        validate();
                        }

                // TMM: 02Jul'01 - changed MapBase<T> to Object in next line
                MapBase<T> (const Object& ob): Object(ob)
                        {
                        validate();
                        }

                // Assignment acquires new ownership of pointer
                MapBase<T>& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                MapBase<T>& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && PyMapping_Check(pyob);
                        }

                // Clear -- PyMapping Clear is missing
                //

                void clear ()
                        {
                        List k = keys();
                        for(List::iterator i = k.begin(); i != k.end(); i++)
                                {
                                delItem(*i);
                                }
                        }

                virtual size_type size() const
                        {
                        return PyMapping_Length (ptr());
                        }

                // Element Access
                T operator[](const std::string& key) const
                        {
                        return getItem(key);
                        }

                T operator[](const Object& key) const
                        {
                        return getItem(key);
                        }

                mapref<T> operator[](const std::string& key)
                        {
                        return mapref<T>(*this, key);
                        }

                mapref<T> operator[](const Object& key)
                        {
                        return mapref<T>(*this, key);
                        }

                int length () const
                        {
                        return PyMapping_Length (ptr());
                        }

                bool hasKey (const std::string& s) const
                        {
                        return PyMapping_HasKeyString (ptr(),const_cast<char*>(s.c_str())) != 0;
                        }

                bool hasKey (const Object& s) const
                        {
                        return PyMapping_HasKey (ptr(), s.ptr()) != 0;
                        }

                T getItem (const std::string& s) const
                        {
                        return T(
                        asObject(PyMapping_GetItemString (ptr(),const_cast<char*>(s.c_str())))
                        );
                        }

                T getItem (const Object& s) const
                        {
                        return T(
                        asObject(PyObject_GetItem (ptr(), s.ptr()))
                        );
                        }

                virtual void setItem (const char *s, const Object& ob)
                        {
                        if (PyMapping_SetItemString (ptr(), const_cast<char*>(s), *ob) == -1)
                                {
                                throw Exception();
                                }
                        }

                virtual void setItem (const std::string& s, const Object& ob)
                        {
                        if (PyMapping_SetItemString (ptr(), const_cast<char*>(s.c_str()), *ob) == -1)
                                {
                                throw Exception();
                                }
                        }

                virtual void setItem (const Object& s, const Object& ob)
                        {
                        if (PyObject_SetItem (ptr(), s.ptr(), ob.ptr()) == -1)
                                {
                                throw Exception();
                                }
                        }

                void delItem (const std::string& s)
                        {
                        if (PyMapping_DelItemString (ptr(), const_cast<char*>(s.c_str())) == -1)
                                {
                                throw Exception();
                                }
                        }

                void delItem (const Object& s)
                        {
                        if (PyMapping_DelItem (ptr(), *s) == -1)
                                {
                                throw Exception();
                                }
                        }
                // Queries
                List keys () const
                        {
                        return List(PyMapping_Keys(ptr()), true);
                        }

                List values () const
                        { // each returned item is a (key, value) pair
                        return List(PyMapping_Values(ptr()), true);
                        }

                List items () const
                        {
                        return List(PyMapping_Items(ptr()), true);
                        }

                // iterators for MapBase<T>
                // Added by TMM: 2Jul'01 - NOT COMPLETED
                // There is still a bug.  I decided to stop, before fixing the bug, because
                // this can't be halfway efficient until Python gets built-in iterators.
                // My current soln is to iterate over the map by getting a copy of its keys
                // and iterating over that.  Not a good solution.

                // The iterator holds a MapBase<T>* rather than a MapBase<T> because that's
                // how the sequence iterator is implemented and it works.  But it does seem
                // odd to me - we are iterating over the map object, not the reference.

#if 0   // here is the test code with which I found the (still existing) bug
                typedef cxx::Dict       d_t;
                d_t     d;
                cxx::String     s1("blah");
                cxx::String     s2("gorf");
                d[ "one" ] = s1;
                d[ "two" ] = s1;
                d[ "three" ] = s2;
                d[ "four" ] = s2;

                d_t::iterator   it;
                it = d.begin();         // this (using the assignment operator) is causing
                // a problem; if I just use the copy ctor it works fine.
                for( ; it != d.end(); ++it )
                        {
                        d_t::value_type vt( *it );
                        cxx::String rs = vt.second.repr();
                        std::string ls = rs.operator std::string();
                        fprintf( stderr, "%s\n", ls );
                        }
#endif // 0

                class iterator
                        {
                        // : public forward_iterator_parent( std::pair<const T,T> ) {
                protected:
                        typedef std::forward_iterator_tag iterator_category;
                        typedef std::pair< const T, T > value_type;
                        typedef int difference_type;
                        typedef std::pair< const T, mapref<T> > pointer;
                        typedef std::pair< const T, mapref<T> > reference;

                        friend class MapBase<T>;
                        //
                        MapBase<T>* map;
                        List    keys;                   // for iterating over the map
                        List::iterator  pos;            // index into the keys

                public:
                        ~iterator ()
                                {}

                        iterator ()
                                : map( 0 )
                                , keys()
                                , pos()
                                {}

                        iterator (MapBase<T>* m, bool end = false )
                                : map( m )
                                , keys( m->keys() )
                                , pos( end ? keys.end() : keys.begin() )
                                {}

                        iterator (const iterator& other)
                                : map( other.map )
                                , keys( other.keys )
                                , pos( other.pos )
                                {}

                        reference operator*()
                                {
                                Object key = *pos;
                                return std::make_pair(key, mapref<T>(*map,key));
                                }

                        iterator& operator=(const iterator& other)
                                {
                                if (this == &other)
                                        return *this;
                                map = other.map;
                                keys = other.keys;
                                pos = other.pos;
                                return *this;
                                }

                        bool eql(const iterator& right) const
                                {
                                return *map == *right.map && pos == right.pos;
                                }
                        bool neq( const iterator& right ) const
                                {
                                return *map != *right.map || pos != right.pos;
                                }

                        // pointer operator->() {
                        //    return ;
                        // }

                        // prefix ++
                        iterator& operator++ ()
                                { pos++; return *this;}
                        // postfix ++
                        iterator operator++ (int)
                                { return iterator(map, keys, pos++);}
                        // prefix --
                        iterator& operator-- ()
                                { pos--; return *this;}
                        // postfix --
                        iterator operator-- (int)
                                { return iterator(map, keys, pos--);}

                        std::string diagnose() const
                                {
                                std::OSTRSTREAM oss;
                                oss << "iterator diagnosis " << map << ", " << pos << std::ends;
                                return std::string(oss.str());
                                }
                        };    // end of class MapBase<T>::iterator

                iterator begin ()
                        {
                        return iterator(this);
                        }

                iterator end ()
                        {
                        return iterator(this, true);
                        }

                class const_iterator
                        {
                protected:
                        typedef std::forward_iterator_tag iterator_category;
                        typedef const std::pair< const T, T > value_type;
                        typedef int difference_type;
                        typedef const std::pair< const T, T > pointer;
                        typedef const std::pair< const T, T > reference;

                        friend class MapBase<T>;
                        const MapBase<T>* map;
                        List    keys;   // for iterating over the map
                        List::iterator  pos;            // index into the keys

                public:
                        ~const_iterator ()
                                {}

                        const_iterator ()
                                : map( 0 )
                                , keys()
                                , pos()
                                {}

                        const_iterator (const MapBase<T>* m, List k, List::iterator p )
                                : map( m )
                                , keys( k )
                                , pos( p )
                                {}

                        const_iterator(const const_iterator& other)
                                : map( other.map )
                                , keys( other.keys )
                                , pos( other.pos )
                                {}

                        bool eql(const const_iterator& right) const
                                {
                                return *map == *right.map && pos == right.pos;
                                }
                        bool neq( const const_iterator& right ) const
                                {
                                return *map != *right.map || pos != right.pos;
                                }


                        //                      const_reference operator*() {
                        //                              Object key = *pos;
                        //                              return std::make_pair( key, map->[key] );
                        // GCC < 3 barfes on this line at the '['.
                        //             }

                        const_iterator& operator=(const const_iterator& other)
                                {
                                if (this == &other) return *this;
                                map = other.map;
                                keys = other.keys;
                                pos = other.pos;
                                return *this;
                                }

                        // prefix ++
                        const_iterator& operator++ ()
                                { pos++; return *this;}
                        // postfix ++
                        const_iterator operator++ (int)
                                { return const_iterator(map, keys, pos++);}
                        // prefix --
                        const_iterator& operator-- ()
                                { pos--; return *this;}
                        // postfix --
                        const_iterator operator-- (int)
                                { return const_iterator(map, keys, pos--);}
                        };    // end of class MapBase<T>::const_iterator

                const_iterator begin () const
                        {
                        return const_iterator(this, 0);
                        }

                const_iterator end () const
                        {
                        return const_iterator(this, length());
                        }

                };      // end of MapBase<T>

        typedef MapBase<Object> Mapping;

        template <TEMPLATE_TYPENAME T> bool operator==(const EXPLICIT_TYPENAME MapBase<T>::iterator& left, const EXPLICIT_TYPENAME MapBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator!=(const EXPLICIT_TYPENAME MapBase<T>::iterator& left, const EXPLICIT_TYPENAME MapBase<T>::iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator==(const EXPLICIT_TYPENAME MapBase<T>::const_iterator& left, const EXPLICIT_TYPENAME MapBase<T>::const_iterator& right);
        template <TEMPLATE_TYPENAME T> bool operator!=(const EXPLICIT_TYPENAME MapBase<T>::const_iterator& left, const EXPLICIT_TYPENAME MapBase<T>::const_iterator& right);

        extern bool operator==(const Mapping::iterator& left, const Mapping::iterator& right);
        extern bool operator!=(const Mapping::iterator& left, const Mapping::iterator& right);
        extern bool operator==(const Mapping::const_iterator& left, const Mapping::const_iterator& right);
        extern bool operator!=(const Mapping::const_iterator& left, const Mapping::const_iterator& right);


        // ==================================================
        // class Dict
        class Dict: public Mapping
                {
        public:
                // Constructor
                explicit Dict (PyObject *pyob, bool owned=false): Mapping (pyob, owned)
                        {
                        validate();
                        }
                Dict (const Dict& ob): Mapping(ob)
                        {
                        validate();
                        }
                // Creation
                Dict ()
                        {
                        set(PyDict_New (), true);
                        validate();
                        }
                // Assignment acquires new ownership of pointer

                Dict& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Dict& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set(rhsp);
                        return *this;
                        }
                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && Py::_Dict_Check (pyob);
                        }
                };

        class Callable: public Object
                {
        public:
                // Constructor
                explicit Callable (): Object()  {}
                explicit Callable (PyObject *pyob, bool owned = false): Object (pyob, owned)
                        {
                        validate();
                        }

                Callable (const Object& ob): Object(ob)
                        {
                        validate();
                        }

                // Assignment acquires new ownership of pointer

                Callable& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Callable& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set (rhsp);
                        return *this;
                        }

                // Membership
                virtual bool accepts (PyObject *pyob) const
                        {
                        return pyob && PyCallable_Check (pyob);
                        }

                // Call
                Object apply(const Tuple& args) const
                        {
                        return asObject(PyObject_CallObject(ptr(), args.ptr()));
                        }

                // Call with keywords
                Object apply(const Tuple& args, const Dict& kw) const
                        {
                        return asObject( PyEval_CallObjectWithKeywords( ptr(), args.ptr(), kw.ptr() ) );
                        }

                Object apply(PyObject* pargs = 0) const
                        {
                        return apply (Tuple(pargs));
                        }
                };

        class Module: public Object
                {
        public:
                explicit Module (PyObject* pyob, bool owned = false): Object (pyob, owned)
                        {
                        validate();
                        }

                // Construct from module name
                explicit Module (const std::string&s): Object()
                        {
                        PyObject *m = PyImport_AddModule( const_cast<char *>(s.c_str()) );
                        set( m, false );
                        validate ();
                        }

                // Copy constructor acquires new ownership of pointer
                Module (const Module& ob): Object(*ob)
                        {
                        validate();
                        }

                Module& operator= (const Object& rhs)
                        {
                        return (*this = *rhs);
                        }

                Module& operator= (PyObject* rhsp)
                        {
                        if(ptr() == rhsp) return *this;
                        set(rhsp);
                        return *this;
                        }

                Dict getDict()
                        {
                        return Dict(PyModule_GetDict(ptr()));
                        // Caution -- PyModule_GetDict returns borrowed reference!
                        }
                };

        // Numeric interface
        inline Object operator+ (const Object& a)
                {
                return asObject(PyNumber_Positive(*a));
                }
        inline Object operator- (const Object& a)
                {
                return asObject(PyNumber_Negative(*a));
                }

        inline Object abs(const Object& a)
                {
                return asObject(PyNumber_Absolute(*a));
                }

        inline std::pair<Object,Object> coerce(const Object& a, const Object& b)
                {
                PyObject *p1, *p2;
                p1 = *a;
                p2 = *b;
                if(PyNumber_Coerce(&p1,&p2) == -1)
                        {
                        throw Exception();
                        }
                return std::pair<Object,Object>(asObject(p1), asObject(p2));
                }

        inline Object operator+ (const Object& a, const Object& b)
                {
                return asObject(PyNumber_Add(*a, *b));
                }
        inline Object operator+ (const Object& a, int j)
                {
                return asObject(PyNumber_Add(*a, *Int(j)));
                }
        inline Object operator+ (const Object& a, double v)
                {
                return asObject(PyNumber_Add(*a, *Float(v)));
                }
        inline Object operator+ (int j, const Object& b)
                {
                return asObject(PyNumber_Add(*Int(j), *b));
                }
        inline Object operator+ (double v, const Object& b)
                {
                return asObject(PyNumber_Add(*Float(v), *b));
                }

        inline Object operator- (const Object& a, const Object& b)
                {
                return asObject(PyNumber_Subtract(*a, *b));
                }
        inline Object operator- (const Object& a, int j)
                {
                return asObject(PyNumber_Subtract(*a, *Int(j)));
                }
        inline Object operator- (const Object& a, double v)
                {
                return asObject(PyNumber_Subtract(*a, *Float(v)));
                }
        inline Object operator- (int j, const Object& b)
                {
                return asObject(PyNumber_Subtract(*Int(j), *b));
                }
        inline Object operator- (double v, const Object& b)
                {
                return asObject(PyNumber_Subtract(*Float(v), *b));
                }

        inline Object operator* (const Object& a, const Object& b)
                {
                return asObject(PyNumber_Multiply(*a, *b));
                }
        inline Object operator* (const Object& a, int j)
                {
                return asObject(PyNumber_Multiply(*a, *Int(j)));
                }
        inline Object operator* (const Object& a, double v)
                {
                return asObject(PyNumber_Multiply(*a, *Float(v)));
                }
        inline Object operator* (int j, const Object& b)
                {
                return asObject(PyNumber_Multiply(*Int(j), *b));
                }
        inline Object operator* (double v, const Object& b)
                {
                return asObject(PyNumber_Multiply(*Float(v), *b));
                }

        inline Object operator/ (const Object& a, const Object& b)
                {
                return asObject(PyNumber_Divide(*a, *b));
                }
        inline Object operator/ (const Object& a, int j)
                {
                return asObject(PyNumber_Divide(*a, *Int(j)));
                }
        inline Object operator/ (const Object& a, double v)
                {
                return asObject(PyNumber_Divide(*a, *Float(v)));
                }
        inline Object operator/ (int j, const Object& b)
                {
                return asObject(PyNumber_Divide(*Int(j), *b));
                }
        inline Object operator/ (double v, const Object& b)
                {
                return asObject(PyNumber_Divide(*Float(v), *b));
                }

        inline Object operator% (const Object& a, const Object& b)
                {
                return asObject(PyNumber_Remainder(*a, *b));
                }
        inline Object operator% (const Object& a, int j)
                {
                return asObject(PyNumber_Remainder(*a, *Int(j)));
                }
        inline Object operator% (const Object& a, double v)
                {
                return asObject(PyNumber_Remainder(*a, *Float(v)));
                }
        inline Object operator% (int j, const Object& b)
                {
                return asObject(PyNumber_Remainder(*Int(j), *b));
                }
        inline Object operator% (double v, const Object& b)
                {
                return asObject(PyNumber_Remainder(*Float(v), *b));
                }

        inline Object type(const Exception&) // return the type of the error
                {
                PyObject *ptype, *pvalue, *ptrace;
                PyErr_Fetch(&ptype, &pvalue, &ptrace);
                Object result(ptype);
                PyErr_Restore(ptype, pvalue, ptrace);
                return result;
                }

        inline Object value(const Exception&) // return the value of the error
                {
                PyObject *ptype, *pvalue, *ptrace;
                PyErr_Fetch(&ptype, &pvalue, &ptrace);
                Object result;
                if(pvalue) result = pvalue;
                PyErr_Restore(ptype, pvalue, ptrace);
                return result;
                }

        inline Object trace(const Exception&) // return the traceback of the error
                {
                PyObject *ptype, *pvalue, *ptrace;
                PyErr_Fetch(&ptype, &pvalue, &ptrace);
                Object result;
                if(ptrace) result = ptrace;
                PyErr_Restore(ptype, pvalue, ptrace);
                return result;
                }



template<TEMPLATE_TYPENAME T>
String seqref<T>::str () const
                        {
                        return the_item.str();
                        }

template<TEMPLATE_TYPENAME T>
String seqref<T>::repr () const
                        {
                        return the_item.repr();
                        }


        } // namespace Py
#endif  // __CXX_Objects__h

---