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42 Implicit and type classes

After reading this lesson, you will be able to

• Define a function that takes implicit parameters using the keyword using
• Mark values as given
• Use the type class pattern to express ad hoc polymorphism

In the previous unit, you learned about collections and error handling. In this lesson, you’ll discover a feature of the Scala language called implicit. It is one of its most controversial traits. On one hand, it allows you to write less code and express extremely powerful abstractions. On the other hand, it can make your program more difficult to understand, and it increases its compilation time if misused. In this lesson, rather than introducing you to all the uses implicits have, you’ll focus on its primary usage. ...