title: Ansible - combining string with an existing variable to register into another variable
body: <p>I want to combine a fact set with <code>set_facts</code> with a string variable and register it as a new variable.</p>
  
  <p>I think, we cannot register a new variable in an Ansible playbook. So can I use <code>set_facts</code> again to combine a previous <code>set_fact</code> with an existing variable?</p>
  
  <p>I am not sure about the syntax here.</p>
  
  <p>Here is an example:</p>
  
  <pre><code>- vars:
      list_1: usera,userb,userc
  </code></pre>
  
  
  
  <pre><code>- set_fact:
      list_2: "userd,usere,userf"
  </code></pre>
  
  <p>Now I want to combine both of the string with comma in between and get a variable value like this:</p>
  
  <pre><code>final_list: usera,userb,userc,userd,usere,userf
  </code></pre>