What are the disadvantages to declaring Scala case classes?

Posted by Graham Lea on Stack Overflow See other posts from Stack Overflow or by Graham Lea
Published on 2011-01-11T01:46:28Z Indexed on 2011/01/11 1:53 UTC
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Filed under:

scala

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case-class

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disadvantages

If you're writing code that's using lots of beautiful, immutable data structures, case classes appear to be a godsend, giving you all of the following for free with just one keyword:

Everything immutable by default
Getters automatically defined
Decent toString() implementation
Compliant equals() and hashCode()
Companion object with unapply() method for matching

But what are the disadvantages of defining an immutable data structure as a case class?

What restrictions does it place on the class or its clients?

Are there situations where you should prefer a non-case class?

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