Object identity, which allows objects to be referenced from other objects in terms of IDs and UUIDs.

By default, in order to allow inline fat-arrow validation functions, the field will not rerender if you change your validation function to an alternate function that has a different behavior. If you need your field to rerender with a new validation function, you will need to update another prop on the Field, such as key

functions present a problem again because there is no reliable way to compare two functions to see if they are semantically equivalent.

React guarantees that setState function identity is stable and won’t change on re-renders. This is why it’s safe to omit from the useEffect or useCallback dependency list.