Add support for defining index var for task loops

docs/docsite/rst/playbooks_loops.rst

@@ -287,6 +287,19 @@ Another option to loop control is ``pause``, which allows you to control the tim
       loop_control:
         pause: 3
 
+.. versionadded:: 2.7
+
+If you need to keep track of where you are in a loop, you can use the ``index_var`` option to loop control to specify a variable name to contain the current loop index.::
+
+    - name: count our fruit
+      debug:
+        msg: "{{ item }} with index {{ my_idx }}"
+      loop:
+        - apple
+        - banana
+        - pear
+      loop_control:
+        index_var: my_idx
 
 .. _loops_and_includes_2.0: