Lookup docs (#30280)

* finalize lookup documentation
* minor fixes to ansible-doc
 - actually show which file caused error on when listing plugins
 - removed redundant display of type and name
* smart quote fixes from toshio

lib/ansible/plugins/lookup/items.py

@@ -1,22 +1,66 @@
 # (c) 2012, Michael DeHaan <michael.dehaan@gmail.com>
-#
-# This file is part of Ansible
-#
-# Ansible is free software: you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
-#
-# Ansible is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
+# (c) 2017 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+DOCUMENTATION = """
+    lookup: items
+    author: Michael DeHaan <michael.dehaan@gmail.com>
+    version_added: historical
+    short_description: list of items
+    description:
+      - this looup returns a list of items given to it, if any of the top level items is also a list it will flatten it, but it will not recurse
+    notes:
+      - this is the standard lookup used for loops in most examples
+      - check out the 'flattened' lookup for recursive flattening
+      - if you dont want flattening nor any other tranformation look at the 'list' lookup.
+    options:
+      _terms:
+        description: list of items
+        required: True
+"""
+
+EXAMPLES = """
+- name: "loop through list"
+  debug: msg="An item: {{item}}"
+  with_items:
+    - 1
+    - 2
+    - 3
+
+- name: add several users
+  user:
+    name: "{{ item }}"
+    groups: "wheel"
+    state: present
+  with_items:
+     - testuser1
+     - testuser2
+
+- name: "loop through list from a variable"
+  debug: msg="An item: {{item}}"
+  with_items: "{{ somelist }}"
+
+- name: more complex items to add several users
+  user:
+    name: "{{ item.name }}"
+    uid: "{{ item.uid }}"
+    groups: "{{ item.groups }}"
+    state: present
+  with_items:
+     - { name: testuser1, uid: 1002, groups: "wheel, staff" }
+     - { name: testuser2, uid: 1003, groups: staff }
+
+"""
+
+RETURN = """
+  _raw:
+    description:
+      - once flattened list
+    type: list
+"""
+
 from ansible.plugins.lookup import LookupBase