how to rewrite this the proper way?

[gregory....@gmail.com]

Hello

here's my playbook, I am looking for interface without IP:

---

- hosts: all

  vars:

    interface_name: ""

    ipaddress: "{{ ansible_default_ipv4.address }}"

  tasks:

  - name: enumerate interfaces

    debug: 

      msg: "{{ item }}"

    with_items:

      "{{ ansible_interfaces }}"

  - debug:

      var:  ansible_{{ item }} 

    with_items:

      "{{ ansible_interfaces }}"

 

  - name: find interface without an ip

    set_fact:

      desired_interface_name: "{{ item }}"

    when:

      ansible_{{ item }}.ipv4 is defined and (ansible_{{ item }}|length>0)

    with_items: 

      "{{ ansible_interfaces }}"

  - name: print result

    debug:

      var: desired_interface_name

it works, but yells me a warn:

[WARNING]: conditional statements should not include jinja2 templating delimiters such as {{ }} or {% %}. Found: ansible_{{item }}.ipv4 is defined and (ansible_{{ item }}|length>0)

just out for curiosity, what's the proper way?

[gregory....@gmail.com]

found a solution myself

 - name: find interface without an ip

    set_fact:

      desired_interface_name: "{{ item }}"

    when:

      hostvars[inventory_hostname]['ansible_'+item].ipv4|length == 0 

      # ansible_{{ item }}.ipv4 is defined and (ansible_{{ item }}|length>0)

    with_items: 

      "{{ ansible_interfaces }}"

it works. although it seems a bit counterintuitive...

why not the first way???