halberom

# /etc/ansible/roles/tmp/tasks/main.yml
---
- name: do something with passed var
  debug: var=myothervar

- name: do something with set_fact var
  debug: var=myvar

halberom

PLAY [all] ********************************************************************

TASK: [register a fact] *******************************************************
ok: [localhost]

PLAY [all] ********************************************************************

TASK: [tmp | do something with passed var] ************************************
ok: [localhost] => {
    "item": "",

halberom

PLAY [all] ********************************************************************

GATHERING FACTS ***************************************************************
ok: [localhost]

TASK: [role1 | set_fact foo=bar] **********************************************
ok: [localhost]

TASK: [role2 | debug var=foo] *************************************************
ok: [localhost] => {

halberom

---
- include: install.yml
  when: 'etcd' in groups

- include: cleanup.yml
  when: 'etcd' not in groups

halberom

# head -n3 roles/hosts-canonical/vars/main.yml 
---
ipaddr_to_hostname:
  10.0.0.2: ['c0w2', 'l2']
  10.0.0.3: ['alt-gateway']

halberom

...
TASK: [debug var=mydate] ******************************************************
ok: [localhost] => {
    "mydate": "20140605101824"
}
...

halberom

# the file doesn't exist

TASK: [debug var=foo] *********************************************************
ok: [localhost] => {
    "foo": {
        "changed": false,
        "invocation": {
            "module_args": "path=/tmp/file",
            "module_name": "stat"
        },

halberom

# roles/do_something/tasks/main.yml
---
- name: do something
  command: grep foo /tmp/bar
  register: result
    
- name: add host to new group based on result
  add_host: hostname=inventory_hostname group_name=mynewgroup
  when: result.stdout == 'whatever'

halberom

---
- hosts: all
  vars:
    mypath: ~/.zprezto/runcoms
  tasks:
    - name: Find runcom Prezto files
      shell: find {{ mypath }} -type f -name 'z*'
      register: file_list
     
    # verify what's returned first 

halberom

TASK: [debug var=source_ip] ***************************************************
ok: [localhost] => {
    "source_ip": "127.0.0.1"
}