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# Optional

* Monad

## why

* To get compile time exceptions rather than runtime exceptions
  * get feed back faster
* when you return something that may or may not exist

## When not to use

* When return a collection, use empty list or the collection
* when the return value is always going to exist
* As a parameter
  * will need to do an `ifPresent` check and pass in the optional
  * use two separate methods (overloading), one with no param and another with the param

## Links

* <https://youtu.be/Ej0sss6cq14?si=89GPkgKS92zlXaMt> Optional - The Mother of All Bikesheds by Stuart Marks