If you include enough in your definition of side effect, everything must have a side effect. Otherwise you wouldn’t be doing it. A pure function that adds two n

If you include enough in your definition of side effect, everything must have a side effect. Otherwise you wouldn’t be doing it. A pure function that adds two numbers and returns the result has left your system in a different state than it was in before it ran. Data binding has side effects and the implementation of the thing doing the binding may cause things to happen, may cause some state to change. But I still wouldn’t consider the declarative data binding itself to have side effects.