# Can we rely on play variables being re-calculated/re-templated for each host in a play? **URL:** \ **Category:** Ansible Project\ **Created:** [July 25, 2016, 8:04pm UTC](https://forum.ansible.com/t/can-we-rely-on-play-variables-being-re-calculated-re-templated-for-each-host-in-a-play/22115 "2016-07-25T20:04:54Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Jonathan\_Strootman](https://avatars.discourse-cdn.com/v4/letter/j/b782af/32.png) [@Jonathan\_Strootman](https://forum.ansible.com/u/Jonathan_Strootman)\ **Post date:** [July 25, 2016, 8:04pm UTC](https://forum.ansible.com/t/can-we-rely-on-play-variables-being-re-calculated-re-templated-for-each-host-in-a-play/22115/1 "2016-07-25T20:04:54Z")
Hello, I know that you _can_, but it seems ambiguous on whether one _should_. For example: There is a role named “role\_1”, which has templated variables in both “defaults/main.yml” and “vars/main.yml”. I could create a playbook which prints those variables for a set of hosts, and the variables would change for each host. For the sake of discussion, here is what those role variables could be: ` ---
**Author:** ![Brian\_Coca](https://avatars.discourse-cdn.com/v4/letter/b/6de8d8/32.png) [@Brian\_Coca](https://forum.ansible.com/u/Brian_Coca)\ **Post date:** [February 28, 2017, 4:19pm UTC](https://forum.ansible.com/t/can-we-rely-on-play-variables-being-re-calculated-re-templated-for-each-host-in-a-play/22115/2 "2017-02-28T16:19:22Z")
Variables are lazily evaluated and computed per host. The issues with set\_fact are that the evaluation is happening before setting the variable as ansible evaluates the expression to pass it to the task: so vars: varname: "{{expression}}" # this is lazy - set\_facts: varname={{expression}} #var is set to result of 'expression' as it is evaluated for the task. I hope that clarifies the issue.