[ffriend]

True in Haskell, but not e.g. in Scala. In Scala, pattern matching is done using partial functions that are defined only for certain patterns. E.g. it's totally legal to write:

  obj match {
    case Foo(x) => ...
    case Bar(y, z) => ...
    // no Baz here
  }

[sampo]

In Scala you get the compiler to check for exhaustive pattern matching if you use case classes and sealed classes. So if you want exhaustiveness checks, you can have them.

[logicfiction]

Not entirely true. You would get a warning if its not exhaustive matching for a sealed trait and you can make warnings into compiler errors with a compiler flag.