Yes, in the context of actions. Actions are already triggered by a subset of all the events available in XForms (form load, value change, click), but they can only run services, and the request for enhancement linked below calls for making actions independent from services:
Indeed, we want to make Form Builder easy to use for people who don't necessarily know about XPath. We took some step towards that goal by adding pre-defined validations to the Control Settings dialog, e.g. or max length. We are planning to add more, and have a UI in the works to express boolean expressions. Using Blocky is an interesting idea; we'll keep that in mind as a possibility.
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