Custom Hooks

    We can compose built-in hooks to create new ones. We should still use the use prefix for our function name.

    We'll see another example of a custom hook when building a drag gesture with PanResponder.


    Here we make a useInterval hook for running a function on a regular interval. It can be deceptively difficult to implement correctly - we should be able to change the delay and callback function at any point.

    Example custom hook from:

    1. Example

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