some progress

[SVN r21610]

doc/counting_iterator_eg.rst

@@ -0,0 +1,35 @@
+
+Example
+-------
+
+This example fills an array with numbers and a second array with
+pointers into the first array, using ``counting_iterator`` for both
+tasks. Finally ``indirect_iterator`` is used to print out the numbers
+into the first array via indirection through the second array.
+
+::
+
+    int N = 7;
+    std::vector<int> numbers;
+    typedef std::vector<int>::iterator n_iter;
+    std::copy(boost::counting_iterator<int>(0),
+             boost::counting_iterator<int>(N),
+             std::back_inserter(numbers));
+
+    std::vector<std::vector<int>::iterator> pointers;
+    std::copy(boost::make_counting_iterator(numbers.begin()),
+	      boost::make_counting_iterator(numbers.end()),
+	      std::back_inserter(pointers));
+
+    std::cout << "indirectly printing out the numbers from 0 to " 
+	      << N << std::endl;
+    std::copy(boost::make_indirect_iterator(pointers.begin()),
+	      boost::make_indirect_iterator(pointers.end()),
+	      std::ostream_iterator<int>(std::cout, " "));
+    std::cout << std::endl;
+
+
+The output is::
+
+    indirectly printing out the numbers from 0 to 7
+    0 1 2 3 4 5 6