Added .begin() and .end() to array2d.

dlib/array2d/array2d_kernel.h

@@ -60,6 +60,9 @@ namespace dlib
          
         typedef T type;
         typedef mem_manager mem_manager_type;
+        typedef T*          iterator;       
+        typedef const T*    const_iterator; 
+
 
         // -----------------------------------
 
@@ -321,6 +324,27 @@ namespace dlib
             return nc_*sizeof(T);
         }
 
+        iterator begin() 
+        {
+            return data;
+        }
+
+        iterator end()
+        {
+            return data+size();
+        }
+
+        const_iterator begin()  const
+        {
+            return data;
+        }
+
+        const_iterator end() const
+        {
+            return data+size();
+        }
+
+
     private:
 
 

dlib/array2d/array2d_kernel_abstract.h

@@ -64,6 +64,8 @@ namespace dlib
 
         typedef T type;
         typedef mem_manager mem_manager_type;
+        typedef T*          iterator;       
+        typedef const T*    const_iterator; 
          
         // ----------------------------------------
 
@@ -255,6 +257,42 @@ namespace dlib
                   An example of such an object is the dlib::cv_image.
         !*/
 
+        iterator begin(
+        );
+        /*!
+            ensures
+                - returns a random access iterator pointing to the first element in this
+                  object.
+                - The iterator will iterate over the elements of the object in row major
+                  order.
+        !*/
+
+        iterator end(
+        );
+        /*!
+            ensures
+                - returns a random access iterator pointing to one past the end of the last
+                  element in this object.
+        !*/
+
+        const_iterator begin(
+        ) const;
+        /*!
+            ensures
+                - returns a random access iterator pointing to the first element in this
+                  object.
+                - The iterator will iterate over the elements of the object in row major
+                  order.
+        !*/
+
+        const_iterator end(
+        ) const;
+        /*!
+            ensures
+                - returns a random access iterator pointing to one past the end of the last
+                  element in this object.
+        !*/
+
     };
 
     template <