2 files changed, 75 insertions, 50 deletions

diff --git a/src/list.h b/src/list.h
index 8f29e85..edbd78c 100644
--- a/src/list.h
+++ b/src/list.h
@@ -149,19 +149,24 @@ namespace Bu
                         friend class List<value, valuealloc, linkalloc>;
                 private:
                         Link *pLink;
-                        iterator() :
-                                pLink( NULL )
+                        MyType &rList;
+                        bool bOffFront;
+                        iterator( MyType &rList ) :
+                                pLink( NULL ),
+                                rList( rList )
                         {
                         }
 
-                        iterator( Link *pLink ) :
-                                pLink( pLink )
+                        iterator( Link *pLink, MyType &rList ) :
+                                pLink( pLink ),
+                                rList( rList )
                         {
                         }
 
                 public:
                         iterator( const iterator &i ) :
-                                pLink( i.pLink )
+                                pLink( i.pLink ),
+                                rList( i.rList )
                         {
                         }
 
@@ -223,43 +228,43 @@ namespace Bu
                                 return pLink->pValue;
                         }
 
-                        /**
-                         * Increment operator.
-                         */
                         iterator &operator++()
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(rList.pFirst):(NULL);
+                                else
                                         pLink = pLink->pNext;
+                                bOffFront = false;
                                 return *this;
                         }
 
-                        /**
-                         * Decrement operator.
-                         */
                         iterator &operator--()
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(NULL):(rList.pLast);
+                                else
                                         pLink = pLink->pPrev;
+                                bOffFront = true;
                                 return *this;
                         }
                         
-                        /**
-                         * Increment operator.
-                         */
                         iterator &operator++( int )
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(rList.pFirst):(NULL);
+                                else
                                         pLink = pLink->pNext;
+                                bOffFront = false;
                                 return *this;
                         }
 
-                        /**
-                         * Decrement operator.
-                         */
                         iterator &operator--( int )
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(NULL):(rList.pLast);
+                                else
                                         pLink = pLink->pPrev;
+                                bOffFront = true;
                                 return *this;
                         }
 
@@ -283,19 +288,24 @@ namespace Bu
                         friend class List<value, valuealloc, linkalloc>;
                 private:
                         Link *pLink;
-                        const_iterator() :
-                                pLink( NULL )
+                        const MyType &rList;
+                        bool bOffFront;
+                        const_iterator( const MyType &rList ) :
+                                pLink( NULL ),
+                                rList( rList )
                         {
                         }
 
-                        const_iterator( Link *pLink ) :
-                                pLink( pLink )
+                        const_iterator( Link *pLink, const MyType &rList ) :
+                                pLink( pLink ),
+                                rList( rList )
                         {
                         }
 
                 public:
                         const_iterator( const iterator &i ) :
-                                pLink( i.pLink )
+                                pLink( i.pLink ),
+                                rList( i.rList )
                         {
                         }
 
@@ -331,29 +341,41 @@ namespace Bu
 
                         const_iterator &operator++()
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(rList.pFirst):(NULL);
+                                else
                                         pLink = pLink->pNext;
+                                bOffFront = false;
                                 return *this;
                         }
 
                         const_iterator &operator--()
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(NULL):(rList.pLast);
+                                else
                                         pLink = pLink->pPrev;
+                                bOffFront = true;
                                 return *this;
                         }
                         
                         const_iterator &operator++( int )
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(rList.pFirst):(NULL);
+                                else
                                         pLink = pLink->pNext;
+                                bOffFront = false;
                                 return *this;
                         }
 
                         const_iterator &operator--( int )
                         {
-                                if( pLink != NULL )
+                                if( pLink == NULL )
+                                        pLink = (bOffFront)?(NULL):(rList.pLast);
+                                else
                                         pLink = pLink->pPrev;
+                                bOffFront = true;
                                 return *this;
                         }
 
@@ -376,16 +398,16 @@ namespace Bu
                  */
                 iterator begin()
                 {
-                        return iterator( pFirst );
+                        return iterator( pFirst, *this );
                 }
 
                 /**
                  * Get a const iterator pointing to the first item in the list.
                  *@returns (const const_iterator)
                  */
-                const const_iterator begin() const
+                const_iterator begin() const
                 {
-                        return const_iterator( pFirst );
+                        return const_iterator( pFirst, *this );
                 }
 
                 /**
@@ -399,27 +421,13 @@ namespace Bu
                 }
 
                 /**
-                 * Erase an item from the list.  After erasing the iterator will point
-                 * to an invalid location and should be ignored.  To erase an item from
-                 * a list in a loop you should create a backup iterator.
-                 *@code
-                 for( List<>::iterator i = l.begin(); i != l.end(); i++ )
-                 {
-                        if( ...(needs delete)... )
-                        {
-                                List<>::iterator prev = i;
-                                prev--;
-                                l.erase( i );
-                                i = prev;
-                                continue;
-                        }
-                 }
-                 @endcode
+                 * Erase an item from the list.
                  *@param i (iterator) The item to erase.
                  */
                 void erase( iterator i )
                 {
                         Link *pCur = i.pLink;
+                        if( pCur == NULL ) return;
                         Link *pPrev = pCur->pPrev;
                         if( pPrev == NULL )
                         {
diff --git a/src/tests/list.cpp b/src/tests/list.cpp
index 12807a5..edbe288 100644
--- a/src/tests/list.cpp
+++ b/src/tests/list.cpp
@@ -18,6 +18,21 @@ int main()
                 l.prepend( -j );
         }
 
+        {
+                Bu::List<int>::iterator i = l.begin();
+                Bu::List<int>::iterator j = i;
+                int a, b;
+                a = *j;
+                printf("end:  %s\n", (j != l.end())?"no":"yes");
+                j--;
+                printf("end:  %s\n", (j != l.end())?"no":"yes");
+                j++;
+                printf("end:  %s\n", (j != l.end())?"no":"yes");
+                i = j;
+                b = *i;
+                printf("%d -> %d\n", a, b );
+        }
+
         for( Bu::List<int>::iterator i = l.begin(); i != l.end(); i++ )
         {
                 printf("%d ", *i );
@@ -25,9 +40,11 @@ int main()
         printf("\n");
         for( Bu::List<int>::iterator i = l.begin(); i != l.end(); i++ )
         {
+                Bu::List<int>::iterator j = i; j--;
                 l.erase( i );
+                i = j;
                 if( i != l.end() )
-                        printf("%d ", *i );
+                        printf("!%d ", *i );
         }
 
         printf("\n\n");