Support for C++11 std::unique_ptr as object pointer

This includes the odb::lazy_unique_ptr implementation.

5 files changed, 645 insertions, 57 deletions

diff --git a/odb/lazy-pointer-traits.hxx b/odb/lazy-pointer-traits.hxx
index 910e1e4..5273db1 100644
--- a/odb/lazy-pointer-traits.hxx
+++ b/odb/lazy-pointer-traits.hxx
@@ -64,8 +64,33 @@ namespace odb
   };
 
 #ifdef ODB_CXX11
+  template <typename T, typename D>
+  class pointer_traits<lazy_unique_ptr<T, D>>
+  {
+  public:
+    static const pointer_kind kind = pk_unique;
+    static const bool lazy = true;
+
+    typedef T element_type;
+    typedef lazy_unique_ptr<element_type, D> pointer_type;
+    typedef std::unique_ptr<element_type, D> eager_pointer_type;
+
+    static bool
+    null_ptr (const pointer_type& p)
+    {
+      return !p;
+    }
+
+    template <class O /* = T */>
+    static typename object_traits<O>::id_type
+    object_id (const pointer_type& p)
+    {
+      return p.object_id<O> ();
+    }
+  };
+
   template <typename T>
-  class pointer_traits<lazy_shared_ptr<T> >
+  class pointer_traits<lazy_shared_ptr<T>>
   {
   public:
     static const pointer_kind kind = pk_shared;
@@ -90,7 +115,7 @@ namespace odb
   };
 
   template <typename T>
-  class pointer_traits<lazy_weak_ptr<T> >
+  class pointer_traits<lazy_weak_ptr<T>>
   {
   public:
     static const pointer_kind kind = pk_weak;
diff --git a/odb/lazy-ptr.hxx b/odb/lazy-ptr.hxx
index c663d4a..0e44066 100644
--- a/odb/lazy-ptr.hxx
+++ b/odb/lazy-ptr.hxx
@@ -101,13 +101,13 @@ namespace odb
 
   // operator< and operator<< are not provided.
   //
-  template<class T, class Y>
+  template <class T, class Y>
   bool operator== (const lazy_ptr<T>&, const lazy_ptr<Y>&);
 
-  template<class T, class Y>
+  template <class T, class Y>
   bool operator!= (const lazy_ptr<T>&, const lazy_ptr<Y>&);
 
-  template<class T> void swap (lazy_ptr<T>&, lazy_ptr<T>&);
+  template <class T> void swap (lazy_ptr<T>&, lazy_ptr<T>&);
 
   // std::auto_ptr lazy version.
   //
@@ -130,10 +130,10 @@ namespace odb
 
     explicit lazy_auto_ptr (T* = 0);
     lazy_auto_ptr (lazy_auto_ptr&);
-    template<class Y> lazy_auto_ptr (lazy_auto_ptr<Y>&);
+    template <class Y> lazy_auto_ptr (lazy_auto_ptr<Y>&);
 
     lazy_auto_ptr& operator= (lazy_auto_ptr&);
-    template<class Y> lazy_auto_ptr& operator= (lazy_auto_ptr<Y>&);
+    template <class Y> lazy_auto_ptr& operator= (lazy_auto_ptr<Y>&);
 
     T& operator* () const;
     T* operator-> () const;
@@ -143,8 +143,8 @@ namespace odb
 
     lazy_auto_ptr (const lazy_auto_ptr_ref<T>&);
     lazy_auto_ptr& operator= (const lazy_auto_ptr_ref<T>&);
-    template<class Y> operator lazy_auto_ptr_ref<Y> ();
-    template<class Y> operator lazy_auto_ptr<Y> ();
+    template <class Y> operator lazy_auto_ptr_ref<Y> ();
+    template <class Y> operator lazy_auto_ptr<Y> ();
 
     // Extension: conversion to bool.
     //
@@ -216,6 +216,133 @@ namespace odb
 
 #ifdef ODB_CXX11
 
+  // C++11 std::unique_ptr lazy version.
+  //
+  template <class T, class D = std::default_delete<T>>
+  class lazy_unique_ptr
+  {
+    // Standard lazy_unique_ptr interface.
+    //
+  public:
+    typedef T* pointer;     // For now assume it is T*.
+    typedef T element_type;
+    typedef D deleter_type;
+
+    /*constexpr*/ lazy_unique_ptr () /*noexcept*/;
+    /*constexpr*/ lazy_unique_ptr (std::nullptr_t) /*noexcept*/;
+    explicit lazy_unique_ptr (pointer) /*noexcept*/;
+
+    // For now assume D is non-reference.
+    //
+    lazy_unique_ptr (pointer, const deleter_type&) /*noexcept*/;
+    lazy_unique_ptr (pointer, deleter_type&&) /*noexcept*/;
+
+    lazy_unique_ptr (lazy_unique_ptr&&) /*noexcept*/;
+    template <class T1, class D1> lazy_unique_ptr (lazy_unique_ptr<T1, D1>&&) /*noexcept*/;
+    template <class T1> lazy_unique_ptr (std::auto_ptr<T1>&&) /*noexcept*/;
+
+    lazy_unique_ptr& operator= (std::nullptr_t) /*noexcept*/;
+    lazy_unique_ptr& operator= (lazy_unique_ptr&&) /*noexcept*/;
+    template <class T1, class D1> lazy_unique_ptr& operator= (lazy_unique_ptr<T1, D1>&&) /*noexcept*/;
+
+    T& operator* () const;
+    pointer operator-> () const /*noexcept*/;
+    pointer get () const /*noexcept*/;
+    explicit operator bool() const /*noexcept*/;
+
+    pointer release () /*noexcept*/;
+    void reset (pointer = pointer ()) /*noexcept*/;
+    void swap (lazy_unique_ptr&) /*noexcept*/;
+
+    deleter_type& get_deleter () /*noexcept*/;
+    const deleter_type& get_deleter () const /*noexcept*/;
+
+    lazy_unique_ptr (const lazy_unique_ptr&) = delete;
+    lazy_unique_ptr& operator= (const lazy_unique_ptr&) = delete;
+
+    // Initialization/assignment from unique_ptr.
+    //
+  public:
+    template <class T1, class D1> lazy_unique_ptr (std::unique_ptr<T1, D1>&&) /*noexcept*/;
+    template <class T1, class D1> lazy_unique_ptr& operator= (std::unique_ptr<T1, D1>&&) /*noexcept*/;
+
+    // Lazy loading interface.
+    //
+  public:
+    typedef odb::database database_type;
+
+    //  NULL      loaded()
+    //
+    //  true       true      NULL pointer to transient object
+    //  false      true      valid pointer to persistent object
+    //  true       false     unloaded pointer to persistent object
+    //  false      false     valid pointer to transient object
+    //
+    bool loaded () const;
+
+    std::unique_ptr<T, D>& load () const;
+
+    // Unload the pointer. For transient objects this function is
+    // equivalent to reset().
+    //
+    void unload () const;
+
+    template <class ID> lazy_unique_ptr (database_type&, const ID&);
+    lazy_unique_ptr (database_type&, pointer);
+    lazy_unique_ptr (database_type&, pointer, const deleter_type&);
+    lazy_unique_ptr (database_type&, pointer, deleter_type&&);
+    template <class T1, class D1> lazy_unique_ptr (database_type&, std::unique_ptr<T1, D1>&&);
+    template <class T1> lazy_unique_ptr (database_type&, std::auto_ptr<T1>&&);
+
+    template <class ID> void reset (database_type&, const ID&);
+    void reset (database_type&, pointer);
+    template <class T1, class D1> void reset (database_type&, std::unique_ptr<T1, D1>&&);
+    template <class T1> void reset (database_type&, std::auto_ptr<T1>&&);
+
+    template <class O = T>
+    typename object_traits<O>::id_type object_id () const;
+
+    database_type& database () const;
+
+    // Helpers.
+    //
+  public:
+    template <class T1, class D1> bool equal (const lazy_unique_ptr<T1, D1>&) const;
+
+  private:
+    template <class T1, class D1> friend class lazy_unique_ptr;
+
+    // Note that it is possible to have a situation where p_ is NULL,
+    // i_.id is NULL and i_.db is not NULL. This will happen if the
+    // unique_ptr reference returned by load() is transferred to
+    // another pointer or reset.
+    //
+    mutable std::unique_ptr<T, D> p_;
+    mutable lazy_ptr_impl<T> i_;
+  };
+
+  template <class T> void swap (lazy_unique_ptr<T>&, lazy_unique_ptr<T>&) /*noexcept*/;
+
+  // operator< and operator<< are not provided.
+  //
+  template <class T1, class D1, class T2, class D2>
+  bool operator== (const lazy_unique_ptr<T1, D1>&, const lazy_unique_ptr<T2, D2>&);
+
+  template <class T, class D>
+  bool operator== (const lazy_unique_ptr<T, D>&, std::nullptr_t) /*noexcept*/;
+
+  template <class T, class D>
+  bool operator== (std::nullptr_t, const lazy_unique_ptr<T, D>&) /*noexcept*/;
+
+  template <class T1, class D1, class T2, class D2>
+  bool operator!= (const lazy_unique_ptr<T1, D1>&, const lazy_unique_ptr<T2, D2>&);
+
+  template <class T, class D>
+  bool operator!= (const lazy_unique_ptr<T, D>&, std::nullptr_t) /*noexcept*/;
+
+  template <class T, class D>
+  bool operator!= (std::nullptr_t, const lazy_unique_ptr<T, D>&) /*noexcept*/;
+
   // C++11 std::shared_ptr lazy version.
   //
   template <class T>
@@ -337,29 +464,29 @@ namespace odb
     mutable lazy_ptr_impl<T> i_;
   };
 
-  template<class T> void swap (lazy_shared_ptr<T>&, lazy_shared_ptr<T>&) /*noexcept*/;
+  template <class T> void swap (lazy_shared_ptr<T>&, lazy_shared_ptr<T>&) /*noexcept*/;
 
-  template<class D, class T>
+  template <class D, class T>
   D* get_deleter (const lazy_shared_ptr<T>&) /*noexcept*/;
 
   // operator< and operator<< are not provided.
   //
-  template<class T, class Y>
+  template <class T, class Y>
   bool operator== (const lazy_shared_ptr<T>&, const lazy_shared_ptr<Y>&) /*noexcept*/;
 
-  template<class T>
+  template <class T>
   bool operator== (const lazy_shared_ptr<T>&, std::nullptr_t) /*noexcept*/;
 
-  template<class T>
+  template <class T>
   bool operator== (std::nullptr_t, const lazy_shared_ptr<T>&) /*noexcept*/;
 
-  template<class T, class Y>
+  template <class T, class Y>
   bool operator!= (const lazy_shared_ptr<T>&, const lazy_shared_ptr<Y>&) /*noexcept*/;
 
-  template<class T>
+  template <class T>
   bool operator!= (const lazy_shared_ptr<T>&, std::nullptr_t) /*noexcept*/;
 
-  template<class T>
+  template <class T>
   bool operator!= (std::nullptr_t, const lazy_shared_ptr<T>&) /*noexcept*/;
 
   // C++11 std::weak_ptr lazy version.
@@ -451,7 +578,7 @@ namespace odb
 
   // operator< is not provided.
   //
-  template<class T> void swap (lazy_weak_ptr<T>&, lazy_weak_ptr<T>&);
+  template <class T> void swap (lazy_weak_ptr<T>&, lazy_weak_ptr<T>&);
 
 #endif // ODB_CXX11
 
@@ -461,6 +588,7 @@ namespace odb
     using odb::lazy_auto_ptr;
 
 #ifdef ODB_CXX11
+    using odb::lazy_unique_ptr;
     using odb::lazy_shared_ptr;
     using odb::lazy_weak_ptr;
 #endif
diff --git a/odb/lazy-ptr.ixx b/odb/lazy-ptr.ixx
index de82a89..5c67845 100644
--- a/odb/lazy-ptr.ixx
+++ b/odb/lazy-ptr.ixx
@@ -190,21 +190,21 @@ namespace odb
     return *i_.database ();
   }
 
-  template<class T, class Y>
+  template <class T, class Y>
   inline bool
   operator== (const lazy_ptr<T>& a, const lazy_ptr<Y>& b)
   {
     return a.equal (b);
   }
 
-  template<class T, class Y>
+  template <class T, class Y>
   inline bool
   operator!= (const lazy_ptr<T>& a, const lazy_ptr<Y>& b)
   {
     return !a.equal (b);
   }
 
-  template<class T>
+  template <class T>
   inline void
   swap (lazy_ptr<T>& a, lazy_ptr<T>& b)
   {
@@ -215,7 +215,7 @@ namespace odb
   // lazy_auto_ptr_ref
   //
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr_ref<T>::
   lazy_auto_ptr_ref (T* p, const lazy_ptr_impl_ref& i): p_ (p), i_ (i) {}
 
@@ -223,26 +223,26 @@ namespace odb
   // lazy_auto_ptr
   //
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (T* p): p_ (p) {}
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (lazy_auto_ptr& r)
       : p_ (r.p_), i_ (static_cast<lazy_ptr_impl_ref> (r.i_))
   {
   }
 
-  template<class T>
-  template<class Y>
+  template <class T>
+  template <class Y>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (lazy_auto_ptr<Y>& r)
       : p_ (r.p_), i_ (static_cast<lazy_ptr_impl_ref> (r.i_))
   {
   }
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>& lazy_auto_ptr<T>::
   operator= (lazy_auto_ptr& r)
   {
@@ -251,8 +251,8 @@ namespace odb
     return *this;
   }
 
-  template<class T>
-  template<class Y>
+  template <class T>
+  template <class Y>
   inline lazy_auto_ptr<T>& lazy_auto_ptr<T>::
   operator= (lazy_auto_ptr<Y>& r)
   {
@@ -261,28 +261,28 @@ namespace odb
     return *this;
   }
 
-  template<class T>
+  template <class T>
   inline T& lazy_auto_ptr<T>::
   operator* () const
   {
     return *p_;
   }
 
-  template<class T>
+  template <class T>
   inline T* lazy_auto_ptr<T>::
   operator-> () const
   {
     return p_.operator-> ();
   }
 
-  template<class T>
+  template <class T>
   inline T* lazy_auto_ptr<T>::
   get () const
   {
     return p_.get ();
   }
 
-  template<class T>
+  template <class T>
   inline T* lazy_auto_ptr<T>::
   release ()
   {
@@ -290,7 +290,7 @@ namespace odb
     return p_.release ();
   }
 
-  template<class T>
+  template <class T>
   inline void lazy_auto_ptr<T>::
   reset (T* p)
   {
@@ -298,11 +298,11 @@ namespace odb
     p_.reset (p);
   }
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (const lazy_auto_ptr_ref<T>& r): p_ (r.p_), i_ (r.i_) {}
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>& lazy_auto_ptr<T>::
   operator= (const lazy_auto_ptr_ref<T>& r)
   {
@@ -313,32 +313,32 @@ namespace odb
     return *this;
   }
 
-  template<class T>
-  template<class Y>
+  template <class T>
+  template <class Y>
   inline lazy_auto_ptr<T>::
   operator lazy_auto_ptr_ref<Y> ()
   {
     return lazy_auto_ptr_ref<Y> (p_.release (), i_);
   }
 
-  template<class T>
-  template<class Y>
+  template <class T>
+  template <class Y>
   inline lazy_auto_ptr<T>::
   operator lazy_auto_ptr<Y> ()
   {
     return lazy_auto_ptr<Y> (*this);
   }
 
-  template<class T>
+  template <class T>
   template <class Y>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (std::auto_ptr<Y>& r): p_ (r) {}
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>::
   lazy_auto_ptr (std::auto_ptr_ref<T> r): p_ (r) {}
 
-  template<class T>
+  template <class T>
   template <class Y>
   inline lazy_auto_ptr<T>& lazy_auto_ptr<T>::
   operator= (std::auto_ptr<Y>& r)
@@ -348,7 +348,7 @@ namespace odb
     return *this;
   }
 
-  template<class T>
+  template <class T>
   inline lazy_auto_ptr<T>& lazy_auto_ptr<T>::
   operator= (std::auto_ptr_ref<T> r)
   {
@@ -413,7 +413,7 @@ namespace odb
   lazy_auto_ptr (database_type& db, std::auto_ptr<Y>& p)
       : p_ (p)
   {
-    if (p)
+    if (p_.get () != 0)
       i_.reset (db);
   }
 
@@ -473,6 +473,357 @@ namespace odb
 #ifdef ODB_CXX11
 
   //
+  // lazy_unique_ptr
+  //
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr () {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (std::nullptr_t) {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (pointer p): p_ (p) {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (pointer p, const deleter_type& d): p_ (p, d) {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (pointer p, deleter_type&& d): p_ (p, std::move (d)) {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (lazy_unique_ptr&& r)
+      : p_ (std::move (r.p_)), i_ (std::move (r.i_)) {}
+
+  template <class T, class D>
+  template <class T1, class D1>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (lazy_unique_ptr<T1, D1>&& r)
+      : p_ (std::move (r.p_)), i_ (std::move (r.i_)) {}
+
+  template <class T, class D>
+  template <class T1>
+  lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (std::auto_ptr<T1>&& r): p_ (std::move (r)) {}
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>& lazy_unique_ptr<T, D>::
+  operator= (std::nullptr_t)
+  {
+    reset ();
+    return *this;
+  }
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>& lazy_unique_ptr<T, D>::
+  operator= (lazy_unique_ptr&& r)
+  {
+    p_ = std::move (r.p_);
+    i_ = std::move (r.i_);
+    return *this;
+  }
+
+  template <class T, class D>
+  template <class T1, class D1>
+  lazy_unique_ptr<T, D>& lazy_unique_ptr<T, D>::
+  operator= (lazy_unique_ptr<T1, D1>&& r)
+  {
+    p_ = std::move (r.p_);
+    i_ = std::move (r.i_);
+    return *this;
+  }
+
+  template <class T, class D>
+  T& lazy_unique_ptr<T, D>::
+  operator* () const
+  {
+    return *p_;
+  }
+
+  template <class T, class D>
+  typename lazy_unique_ptr<T, D>::pointer lazy_unique_ptr<T, D>::
+  operator-> () const
+  {
+    return p_.operator-> ();
+  }
+
+  template <class T, class D>
+  typename lazy_unique_ptr<T, D>::pointer lazy_unique_ptr<T, D>::
+  get () const
+  {
+    return p_.get ();
+  }
+
+  template <class T, class D>
+  lazy_unique_ptr<T, D>::
+  operator bool() const
+  {
+    return p_ || i_;
+  }
+
+  template <class T, class D>
+  typename lazy_unique_ptr<T, D>::pointer lazy_unique_ptr<T, D>::
+  release ()
+  {
+    i_.reset ();
+    return p_.release ();
+  }
+
+  template <class T, class D>
+  void lazy_unique_ptr<T, D>::
+  reset (pointer p)
+  {
+    p_.reset (p);
+    i_.reset ();
+  }
+
+  template <class T, class D>
+  void lazy_unique_ptr<T, D>::
+  swap (lazy_unique_ptr& b)
+  {
+    p_.swap (b.p_);
+    i_.swap (b.i_);
+  }
+
+  template <class T, class D>
+  typename lazy_unique_ptr<T, D>::deleter_type& lazy_unique_ptr<T, D>::
+  get_deleter ()
+  {
+    return p_.get_deleter ();
+  }
+
+  template <class T, class D>
+  const typename lazy_unique_ptr<T, D>::deleter_type& lazy_unique_ptr<T, D>::
+  get_deleter () const
+  {
+    return p_.get_deleter ();
+  }
+
+  template <class T, class D>
+  template <class T1, class D1>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (std::unique_ptr<T1, D1>&& p)
+      : p_ (std::move (p))
+  {
+  }
+
+  template <class T, class D>
+  template <class T1, class D1>
+  inline lazy_unique_ptr<T, D>& lazy_unique_ptr<T, D>::
+  operator= (std::unique_ptr<T1, D1>&& p)
+  {
+    p_ = std::move (p);
+    i_.reset ();
+    return *this;
+  }
+
+  template <class T, class D>
+  inline bool lazy_unique_ptr<T, D>::
+  loaded () const
+  {
+    bool i (i_);
+    return !p_ != i; // !p_ XOR i_
+  }
+
+  template <class T, class D>
+  inline std::unique_ptr<T, D>& lazy_unique_ptr<T, D>::
+  load () const
+  {
+    if (!loaded ())
+      p_ = std::unique_ptr<T, D> (i_.template load<T> (true)); // Reset id.
+
+    return p_;
+  }
+
+  template <class T, class D>
+  inline void lazy_unique_ptr<T, D>::
+  unload () const
+  {
+    typedef typename object_traits<T>::object_type object_type;
+
+    if (p_)
+    {
+      if (i_.database () != 0)
+        i_.reset_id (object_traits<object_type>::id (*p_));
+
+      p_.reset ();
+    }
+  }
+
+  template <class T, class D>
+  template <class ID>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, const ID& id): i_ (db, id) {}
+
+  template <class T, class D>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, T* p)
+      : p_ (p)
+  {
+    if (p_)
+      i_.reset (db);
+  }
+
+  template <class T, class D>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, T* p, const deleter_type& d)
+      : p_ (p, d)
+  {
+    if (p_)
+      i_.reset (db);
+  }
+
+  template <class T, class D>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, T* p, deleter_type&& d)
+      : p_ (p, std::move (d))
+  {
+    if (p_)
+      i_.reset (db);
+  }
+
+  template <class T, class D>
+  template <class T1, class D1>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, std::unique_ptr<T1, D1>&& p)
+      : p_ (std::move (p))
+  {
+    if (p_)
+      i_.reset (db);
+  }
+
+  template <class T, class D>
+  template <class T1>
+  inline lazy_unique_ptr<T, D>::
+  lazy_unique_ptr (database_type& db, std::auto_ptr<T1>&& p)
+      : p_ (std::move (p))
+  {
+    if (p_)
+      i_.reset (db);
+  }
+
+  template <class T, class D>
+  template <class ID>
+  inline void lazy_unique_ptr<T, D>::
+  reset (database_type& db, const ID& id)
+  {
+    p_.reset ();
+    i_.reset (db, id);
+  }
+
+  template <class T, class D>
+  inline void lazy_unique_ptr<T, D>::
+  reset (database_type& db, T* p)
+  {
+    p_.reset (p);
+
+    if (p)
+      i_.reset (db);
+    else
+      i_.reset ();
+  }
+
+  template <class T, class D>
+  template <class T1, class D1>
+  inline void lazy_unique_ptr<T, D>::
+  reset (database_type& db, std::unique_ptr<T1, D1>&& p)
+  {
+    p_ = std::move (p);
+
+    if (p_)
+      i_.reset (db);
+    else
+      i_.reset ();
+  }
+
+  template <class T, class D>
+  template <class T1>
+  inline void lazy_unique_ptr<T, D>::
+  reset (database_type& db, std::auto_ptr<T1>&& p)
+  {
+    p_ = std::unique_ptr<T, D> (std::move (p));
+
+    if (p_)
+      i_.reset (db);
+    else
+      i_.reset ();
+  }
+
+  template <class T, class D>
+  template <class O>
+  inline typename object_traits<O>::id_type lazy_unique_ptr<T, D>::
+  object_id () const
+  {
+    typedef typename object_traits<T>::object_type object_type;
+
+    return p_ ? object_traits<object_type>::id (*p_) : i_.object_id<O> ();
+  }
+
+  template <class T, class D>
+  inline typename lazy_unique_ptr<T, D>::database_type& lazy_unique_ptr<T, D>::
+  database () const
+  {
+    return *i_.database ();
+  }
+
+  template <class T>
+  inline void
+  swap (lazy_unique_ptr<T>& a, lazy_unique_ptr<T>& b)
+  {
+    a.swap (b);
+  }
+
+  template <class T1, class D1, class T2, class D2>
+  inline bool
+  operator== (const lazy_unique_ptr<T1, D1>& a,
+              const lazy_unique_ptr<T2, D2>& b)
+  {
+    return a.equal (b);
+  }
+
+  template <class T, class D>
+  inline bool
+  operator== (const lazy_unique_ptr<T, D>& a, std::nullptr_t)
+  {
+    return !a;
+  }
+
+  template <class T, class D>
+  inline bool
+  operator== (std::nullptr_t, const lazy_unique_ptr<T, D>& b)
+  {
+    return !b;
+  }
+
+  template <class T1, class D1, class T2, class D2>
+  inline bool
+  operator!= (const lazy_unique_ptr<T1, D1>& a,
+              const lazy_unique_ptr<T2, D2>& b)
+  {
+    return !a.equal (b);
+  }
+
+  template <class T, class D>
+  inline bool
+  operator!= (const lazy_unique_ptr<T, D>& a, std::nullptr_t)
+  {
+    return a;
+  }
+
+  template <class T, class D>
+  inline bool
+  operator!= (std::nullptr_t, const lazy_unique_ptr<T, D>& b)
+  {
+    return b;
+  }
+
+  //
   // lazy_shared_ptr
   //
 
@@ -953,56 +1304,56 @@ namespace odb
     return *i_.database ();
   }
 
-  template<class T, class Y>
+  template <class T, class Y>
   inline bool
   operator== (const lazy_shared_ptr<T>& a, const lazy_shared_ptr<Y>& b)
   {
     return a.equal (b);
   }
 
-  template<class T>
+  template <class T>
   inline bool
   operator== (const lazy_shared_ptr<T>& p, std::nullptr_t)
   {
     return !p;
   }
 
-  template<class T>
+  template <class T>
   inline bool
   operator== (std::nullptr_t, const lazy_shared_ptr<T>& p)
   {
     return !p;
   }
 
-  template<class T, class Y>
+  template <class T, class Y>
   inline bool
   operator!= (const lazy_shared_ptr<T>& a, const lazy_shared_ptr<Y>& b)
   {
     return !a.equal (b);
   }
 
-  template<class T>
+  template <class T>
   inline bool
   operator!= (const lazy_shared_ptr<T>& p, std::nullptr_t)
   {
     return p;
   }
 
-  template<class T>
+  template <class T>
   inline bool
   operator!= (std::nullptr_t, const lazy_shared_ptr<T>& p)
   {
     return p;
   }
 
-  template<class T>
+  template <class T>
   inline void
   swap (lazy_shared_ptr<T>& a, lazy_shared_ptr<T>& b)
   {
     a.swap (b);
   }
 
-  template<class D, class T>
+  template <class D, class T>
   inline D*
   get_deleter (const lazy_shared_ptr<T>& p)
   {
@@ -1244,7 +1595,7 @@ namespace odb
     return *i_.database ();
   }
 
-  template<class T>
+  template <class T>
   inline void
   swap (lazy_weak_ptr<T>& a, lazy_weak_ptr<T>& b)
   {
diff --git a/odb/lazy-ptr.txx b/odb/lazy-ptr.txx
index 2265fec..fdc304b 100644
--- a/odb/lazy-ptr.txx
+++ b/odb/lazy-ptr.txx
@@ -42,6 +42,41 @@ namespace odb
 #ifdef ODB_CXX11
 
   //
+  // lazy_unique_ptr
+  //
+
+  template <class T, class D>
+  template <class T1, class D1>
+  bool lazy_unique_ptr<T, D>::
+  equal (const lazy_unique_ptr<T1, D1>& r) const
+  {
+    bool t1 (!p_ == loaded ());
+    bool t2 (!r.p_ == r.loaded ());
+
+    // If both are transient, then compare the underlying pointers.
+    //
+    if (t1 && t2)
+      return p_ == r.p_;
+
+    // If one is transient and the other is persistent, then compare
+    // the underlying pointers but only if they are non NULL. Note
+    // that an unloaded persistent object is always unequal to a
+    // transient object.
+    //
+    if (t1 || t2)
+      return p_ == r.p_ && p_;
+
+    // If both objects are persistent, then we compare databases and
+    // object ids.
+    //
+    typedef typename object_traits<T>::object_type object_type1;
+    typedef typename object_traits<T1>::object_type object_type2;
+
+    return i_.database () == r.i_.database () &&
+      object_id<object_type1> () == r.object_id<object_type2> ();
+  }
+
+  //
   // lazy_shared_ptr
   //
 
diff --git a/odb/pointer-traits.hxx b/odb/pointer-traits.hxx
index 07b396a..fbfa721 100644
--- a/odb/pointer-traits.hxx
+++ b/odb/pointer-traits.hxx
@@ -8,7 +8,7 @@
 #include <odb/pre.hxx>
 
 #include <new>     // operators new/delete
-#include <memory>  // std::auto_ptr, std::shared_ptr (C++11)
+#include <memory>  // std::auto_ptr, std::unique_ptr, std::shared_ptr/weak_ptr
 #include <cstddef> // std::size_t
 
 #include <odb/details/config.hxx>            // ODB_CXX11
@@ -193,10 +193,59 @@ namespace odb
 
 #ifdef ODB_CXX11
 
+  // Specialization for C++11 std::unique_ptr.
+  //
+  template <typename T, typename D>
+  class pointer_traits<std::unique_ptr<T, D>>
+  {
+  public:
+    static const pointer_kind kind = pk_unique;
+    static const bool lazy = false;
+
+    typedef T element_type;
+    typedef std::unique_ptr<element_type, D> pointer_type;
+    typedef std::unique_ptr<const element_type, D> const_pointer_type;
+    typedef smart_ptr_guard<pointer_type> guard;
+
+    static element_type*
+    get_ptr (const pointer_type& p)
+    {
+      return p.get ();
+    }
+
+    static element_type&
+    get_ref (const pointer_type& p)
+    {
+      return *p;
+    }
+
+    static bool
+    null_ptr (const pointer_type& p)
+    {
+      return !p;
+    }
+
+    // cast() is not provided since it transfers the ownership.
+    //
+
+  public:
+    static void*
+    allocate (std::size_t n)
+    {
+      return operator new (n);
+    }
+
+    static void
+    free (void* p)
+    {
+      operator delete (p);
+    }
+  };
+
   // Specialization for C++11 std::shared_ptr.
   //
   template <typename T>
-  class pointer_traits<std::shared_ptr<T> >
+  class pointer_traits<std::shared_ptr<T>>
   {
   public:
     static const pointer_kind kind = pk_shared;
@@ -252,7 +301,7 @@ namespace odb
   // Specialization for C++11 std::weak_ptr.
   //
   template <typename T>
-  class pointer_traits<std::weak_ptr<T> >
+  class pointer_traits<std::weak_ptr<T>>
   {
   public:
     static const pointer_kind kind = pk_weak;