functional programming - What is the difference between Scala's case class and class?

Question

I searched in Google to find the differences between a case class and a class. Everyone mentions that when you want to do pattern matching on the class, use case class. Otherwise use classes and also mentioning some extra perks like equals and hash code overriding. But are these the only reasons why one should use a case class instead of class?

I guess there should be some very important reason for this feature in Scala. What is the explanation or is there a resource to learn more about the Scala case classes from?

Answer 1

Case classes can be seen as plain and immutable data-holding objects that should exclusively depend on their constructor arguments.

This functional concept allows us to

• use a compact initialization syntax (Node(1, Leaf(2), None)))
• decompose them using pattern matching
• have equality comparisons implicitly defined

In combination with inheritance, case classes are used to mimic algebraic datatypes.

If an object performs stateful computations on the inside or exhibits other kinds of complex behaviour, it should be an ordinary class.