How to read a particular part of file in ansible

Question

I have a file which has the following data

!

multiply 4 and 5

multiply 5 and 6

!

add 3 to 4

<

Answer 1

Use with_lines. The play below

- hosts: localhost
  vars:
    my_data_file: "{{ playbook_dir }}/data.txt"
    my_commands: []
  tasks:
    - set_fact:
        my_commands: "{{ my_commands + [ item ] }}"
      with_lines: "cat {{ my_data_file }}"
      when: item is search('^add')
    - debug:
        var: my_commands

gives

"my_commands": [
    "add 3 to 4", 
    "add 8 to 4"
]