Expand our previous example with the expression, which defines the due date of a child task based on the parent worfklow task/doc priority. The expression adds the predefined duration to the current date. Duration is represented in ISO format. Perform the steps 1-4 as described in the previous example and then type the following expression as predefined rule for the due date:
If ($parent->Priority == ID(“Priority.values.Low”),
If ($parent->Priority == ID(“Priority.values.Medium”),
With this expression, the higher priority is selected, the less task duration is specified. To check how it works, create a new workflow task, select its priority and move it through workflow. On the required step the child task will be created with the due date set according to the predefined rule.