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    Get Acquainted with Functor Data Types in JavaScript by creating an Identity Functor

    The term functor comes from category theory in which a functor is a date type used to preserve the structure of data as it's transformed from one category to another. We can recreate these data types in JavaScript by using regular factory functions.

    In this lesson, we learn about the properties our data type must have in order to be considered a true functor. By the end of the lesson you will have created a factory function for creating Identity functors.