updating docs

operators/kind.md

@@ -1,3 +1,10 @@
+# Kind
+
+The `kind` operator identifies the type of a node as either `scalar`, `map`, or `seq`.
+
+This can be used for filtering or transforming nodes based on their type.
+
+Note that `null` values are treated as `scalar`.
 
 ## Get kind
 Given a sample.yml file of:

operators/pick.md

@@ -26,6 +26,30 @@ myMap:
   cat: meow
 ```
 
+## Pick keys from map, included all the keys
+We create a map of the picked keys plus all the current keys, and run that through unique
+
+Given a sample.yml file of:
+```yaml
+myMap:
+  cat: meow
+  dog: bark
+  thing: hamster
+  hamster: squeak
+```
+then
+```bash
+yq '.myMap |= pick( (["thing"] + keys) | unique)' sample.yml
+```
+will output
+```yaml
+myMap:
+  thing: hamster
+  cat: meow
+  dog: bark
+  hamster: squeak
+```
+
 ## Pick indices from array
 Note that the order of the indices matches the pick order and non existent indices are skipped.