Group and object by key and possible subkey

returns {(key to group by) : [{(secondary key) : (key to group by)}]}

groupArrayOfObjectsByKey(Array , String key, [String key2])

Union / Enum for JS

java like enum can be used for pointer type function ex. https://dev.to/avalander/union-types-with-javascript-4emo

Union Example

Print

https://github.com/14paxton/printDiv/blob/main/PrintElement.js