# in Ansible 1.2 and later, the $foo variable syntax, which is friendly enough for simple things
# has been upgraded to allow Jinja2 substitiutions as well, which is now the preferred Syntax.
# here is an example.  Note that Jinja2 conditionals belong only in templates.  Use ansible conditionals
# in playbooks.

---

  - hosts: all
    vars:
      a: '{{ ansible_os_family }}'
      b: 'cat'
      c: '{{ ansible_os_family }} / {{ a }}'
      d: '{{ c }} / {{ a }}'
      e: '{{ d }} / {{ ansible_hostname }}'
      

    tasks:

      - debug: msg={{ e }}

      - shell: echo '{{ e }}'