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diff --git a/src/stlplus/containers/simple_ptr.hpp b/src/stlplus/containers/simple_ptr.hpp
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+#ifndef STLPLUS_SIMPLE_PTR
+#define STLPLUS_SIMPLE_PTR
+////////////////////////////////////////////////////////////////////////////////
+
+//   Author:    Daniel Milton, Andy Rushton
+//   Copyright: (c) Southampton University 1999-2004
+//              (c) Daniel Milton, Andy Rushton 2004-2009
+//   License:   BSD License, see ../docs/license.html
+
+//   A smart pointer is a memory-managing pointer to an object. If you like, it
+//   is a zero-dimensional container.
+
+//   Assignment of smart pointers result in multiple aliases of the same object.
+//   The term alias is used to differentiate from conventional pointers because
+//   the semantics are different.
+
+//   Aliases can be turned into copies if the pointed-to class supports copying.
+
+//   These simple_ptr classes from DJDM have slightly different semantics than
+//   the smart_ptr classes of AJR. There are no cross-pointer side effects
+//   that occur when the pointer is cleared. The clear() function is effectively
+//   equivalent to the clear_unique() function of the smart_ptr. The only way
+//   that a "referenced" object will be deleted is if all simple_ptr's that
+//   reference the object are cleared (by deletion, manual clearing or reassignment).
+
+//   Also, the simple pointer cannot contain a reference to a shared null pointer
+//   (which occurs as a side-effect of clearing a multiply referenced object in
+//   the smart_ptr classes). Which means that if you have a null simple_ptr, then
+//   the assignment of any other null simple_ptr will NOT reassign the reference of
+//   any other simple_ptr. Hence, the simple_ptr class acts a little more like a
+//   normal pointer (with fewer side effects), with the added bonus of containment.
+
+//   Due to the way that the simple_ptr contains the data, it also allows the
+//   addition of various casting functions, while still keeping the managed data
+//   containment functionality of the underlying object. This means that you can
+//   have two simple_ptr's of different template types, both pointing to the same
+//   data (if the differing template types are derivatives of each other).
+
+//   The base class is simple_ptr_base which defines the common interface. Then
+//   there are three subclasses which have the same interface but different copy
+//   semantics:
+
+//   - simple_ptr        for simple types and classes which have copy constructors
+//   - simple_ptr_clone  for polymorphic class hierarchies which are copied using a clone method
+//   - simple_ptr_nocopy for any class that cannot or should not be copied
+
+////////////////////////////////////////////////////////////////////////////////
+#include "containers_fixes.hpp"
+#include "exceptions.hpp"
+#include "copy_functors.hpp"
+#include <map>
+#include <string>
+
+namespace stlplus
+{
+
+  ////////////////////////////////////////////////////////////////////////////////
+  // Base class
+  ////////////////////////////////////////////////////////////////////////////////
+
+  template<typename T, typename C>
+  class simple_ptr_base
+  {
+  public:
+    //////////////////////////////////////////////////////////////////////////////
+    // member type definitions
+
+    typedef T value_type;
+    typedef T& reference;
+    typedef const T& const_reference;
+    typedef C value_copy;
+
+    //////////////////////////////////////////////////////////////////////////////
+    // constructors and destructors
+
+    // create a null pointer
+    simple_ptr_base(void);
+
+    // create a pointer containing a *copy* of the object using the template parameter C
+    // this copy is taken because the pointer class maintains a dynamically allocated object
+    // and the T& may not be (usually is not) dynamically allocated
+    explicit simple_ptr_base(const T& data) throw(illegal_copy);
+
+    // create a pointer containing a dynamically created object
+    // Note: the object must be allocated *by the user* with new
+    // constructor form - must be called in the form smart_ptr_base<type> x(new type(args))
+    explicit simple_ptr_base(T* data);
+
+    // copy constructor implements aliasing so no copy is made
+    // note that the copy constructor should NOT be explicit, as this breaks
+    // the returning of pointer objects from functions (at least within GCC 4.4)
+    simple_ptr_base(const simple_ptr_base<T,C>& r);
+
+    // assignment operator - required, else the output of GCC suffers segmentation faults
+    simple_ptr_base<T,C>& operator=(const simple_ptr_base<T,C>& r);
+
+    // destructor decrements the reference count and delete only when the last reference is destroyed
+    ~simple_ptr_base(void);
+
+    //////////////////////////////////////////////////////////////////////////////
+    // logical tests to see if there is anything contained in the pointer since it can be null
+
+    // there are two forms:explicit and implicit
+    // implicit: if(!r) or if(r)
+    // explicit: if(r.null()) or if(r.present())
+    operator bool(void) const;
+    bool operator!(void) const;
+    bool present(void) const;
+    bool null(void) const;
+
+    //////////////////////////////////////////////////////////////////////////////
+    // dereference operators and functions
+
+    // dereference the smart pointer to get the object - use in the form *p1
+    T& operator*(void) throw(null_dereference);
+    const T& operator*(void) const throw(null_dereference);
+
+    // used as a prefix to a member access to the contained object e.g. p1->print() calls T::print()
+    T* operator->(void) throw(null_dereference);
+    const T* operator->(void) const throw(null_dereference);
+
+    //////////////////////////////////////////////////////////////////////////////
+    // explicit function forms of the above assignment and dereference operators
+
+    // set the value - note that this does a copy using the C template parameter
+    void set_value(const T& data) throw(illegal_copy);
+    // get the value
+    T& value(void) throw(null_dereference);
+    const T& value(void) const throw(null_dereference);
+
+    // set the pointer
+    // deletes the previous pointer and adopts the passed pointer instead
+    // Note: the object must be allocated *by the user* with new
+    // Warning: it is very easy to break the memory management with this operation
+    void set(T* data = 0);
+    // get the pointer
+    T* pointer(void);
+    const T* pointer(void) const;
+
+    //////////////////////////////////////////////////////////////////////////////
+    // functions to manage aliases
+
+    // make this an alias of the passed object
+    void alias(const simple_ptr_base<T,C>&);
+
+    // test whether two pointers point to the same object(known as aliasing the object)
+    // used in the form if(a.aliases(b))
+    bool aliases(const simple_ptr_base<T,C>&) const;
+
+    // find the number of aliases - used when you need to know whether an
+    // object is still referred to from elsewhere (rare!)
+    unsigned alias_count(void) const;
+
+    // clear the reference to the object, but only delete the object if there are no
+    // other references to that object. Hence, this does not affect other pointers
+    // that are pointing to the same object.
+    void clear(void);
+
+    // This is just an alias of the clear() function, provided for completeness of
+    // the interface when acting as a replacement for the smart_ptr classes
+    void clear_unique(void);
+
+    //////////////////////////////////////////////////////////////////////////////
+    // functions that involve copying
+
+    // these functions use the copy functor passed as the template parameter C
+    // to copy the object with the right copy semantics. If the copy functor
+    // is no_copy, an exception will be thrown.
+
+    // make this pointer unique with respect to any other references to the same object
+    // if this pointer is already unique, it does nothing - otherwise it copies the object
+    void make_unique(void) throw(illegal_copy);
+
+    // make this pointer a unique copy of the parameter
+    // useful for expressions like p1.copy(p2) which makes p1 a pointer to a unique copy of the contents of p2
+    void copy(const simple_ptr_base<T,C>&) throw(illegal_copy);
+
+    //////////////////////////////////////////////////////////////////////////////
+    // functions that involve casting
+
+#ifdef STLPLUS_MEMBER_TEMPLATES
+
+    // dynamic cast of underlying pointer to a derived/parent
+    template<typename T2> simple_ptr_base<T2,C> dyn_cast(void) const;
+
+    // static cast of underlying pointer to a derived/parent
+    template<typename T2> simple_ptr_base<T2,C> stat_cast(void) const;
+
+    // cast of underlying pointer to a base - while keeping the same ref-counted object
+    template<typename T2> simple_ptr_base<T2,C> cast(void) const;
+
+#endif
+
+    //////////////////////////////////////////////////////////////////////////////
+
+  protected:
+    T* m_pointer;
+    unsigned* m_count;
+
+  public:
+    // internal use only - had to make them public because they need to be
+    // accessed by routines that could not be made friends
+    // can't have a handle due to the way the simple pointer stores it's data
+    // in separate counter and pointer objects
+    unsigned* _count(void) const;
+    T* _pointer(void) const;
+    void _make_alias(T* pointer, unsigned* count);
+
+  private:
+    void increment(void);
+    bool decrement(void);
+  };
+
+  ////////////////////////////////////////////////////////////////////////////////
+  // simple_ptr        for simple types and classes which have copy constructors
+
+  template <typename T>
+  class simple_ptr : public simple_ptr_base<T, constructor_copy<T> >
+  {
+  public:
+    simple_ptr(void) {}
+    explicit simple_ptr(const T& data) : simple_ptr_base<T, constructor_copy<T> >(data) {}
+    explicit simple_ptr(T* data) : simple_ptr_base<T, constructor_copy<T> >(data) {}
+    simple_ptr<T>& operator=(const T& data) {set_value(data); return *this;}
+    simple_ptr<T>& operator=(T* data) {set(data); return *this;}
+    ~simple_ptr(void) {}
+  };
+
+  ////////////////////////////////////////////////////////////////////////////////
+  // smart_ptr_clone  for polymorphic class hierarchies which have a clone method
+
+  template <typename T>
+  class simple_ptr_clone : public simple_ptr_base<T, clone_copy<T> >
+  {
+  public:
+    simple_ptr_clone(void) {}
+    explicit simple_ptr_clone(const T& data) : simple_ptr_base<T, clone_copy<T> >(data) {}
+    explicit simple_ptr_clone(T* data) : simple_ptr_base<T, clone_copy<T> >(data) {}
+    simple_ptr_clone<T>& operator=(const T& data) {set_value(data); return *this;}
+    simple_ptr_clone<T>& operator=(T* data) {set(data); return *this;}
+    ~simple_ptr_clone(void) {}
+  };
+
+  ////////////////////////////////////////////////////////////////////////////////
+  // smart_ptr_nocopy for any class that cannot or should not be copied
+
+  template <typename T>
+  class simple_ptr_nocopy : public simple_ptr_base<T, no_copy<T> >
+  {
+  public:
+    simple_ptr_nocopy(void) {}
+    explicit simple_ptr_nocopy(const T& data) : simple_ptr_base<T, no_copy<T> >(data) {}
+    explicit simple_ptr_nocopy(T* data) : simple_ptr_base<T, no_copy<T> >(data) {}
+    simple_ptr_nocopy<T>& operator=(const T& data) {set_value(data); return *this;}
+    simple_ptr_nocopy<T>& operator=(T* data) {set(data); return *this;}
+    ~simple_ptr_nocopy(void) {}
+  };
+
+  ////////////////////////////////////////////////////////////////////////////////
+
+} // end namespace stlplus
+
+#include "simple_ptr.tpp"
+#endif