case class overloading in Scala -


i have legacy message in system, , able map new version message in system.

why can't overload case class?

case class message(a:int, b:int) case class newmessage(a:int, b:int, c:int) {   def this(msg : message) = this(a = msg.a, b = msg.b, c = 0) } val msg = message(1,2) val converted = newmessage(msg)

this code doesn't seem compile. :(

you must explicitly call constructor using new operator:

val converted = new newmessage(msg)

it works because defining second constructor in newmessage while ordinary:

newmessage(1, 2, 3)

is translated to:

newmessage.apply(1, 2, 3)

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