README

README.md

@@ -159,6 +159,29 @@ foreach ($fruits as $name => $data) {
 > `results` at a time. It is always one item in memory at a time at the level/subtree
 > you are currently iterating. Thus, the memory consumption is constant.
 
+Json Pointer spec also allows using hyphen (`-`) instead of specific value of an array index. Json Machine interprets
+this as a wildcard which matches any **array index** (not any object key). This enables you to iterate nested values in
+arrays without loading the whole item.
+
+Example:
+```json
+// fruitsArray.json
+{
+    "results": [
+        {
+            "name": "apple",
+            "color": "red"
+        },
+        {
+            "name": "pear",
+            "color": "yellow"
+        }
+    ]
+}
+```
+
+To iterate over all colors of the fruits use json pointer `"/results/-/color"`.
+
 <a name="json-pointer"></a>
 #### What is Json Pointer?
 It's a way of addressing one item in JSON document. See the [Json Pointer RFC 6901](https://tools.ietf.org/html/rfc6901).