ansible/ansible — pull request #1247 by dagwieers (2012-10-06 18:42:11+00:00)
Title: Added eval option to debug module to evaluate an expression

Using this new eval= option, users can have the debug module bail out if the evaluation fails, or explicitely continue (using fail=no). The module will return the result of the evaluation as well as the original templated string. This helps test evaluations, both showing what is evaluated as well as the result.