scala - Call to == does not opt to equals -


i have following class:

abstract class irdmessage extends ordered[irdmessage] {    val messagetype: messagetype.type   val timestamp: datetime   val content: anyref    def compare(that: irdmessage): int = {     val res = timestamp compareto that.timestamp     res   }    override def equals(obj: any): boolean = obj match{     case message: irdmessage => compareto(message) == 0     case _ => false   }  }

i have couple of concrete implementations well. however, when try a == b of subtype of irdmessage equals method not called , compares references (default equals implementation). ideas might causing this?

the subclasses simple case classes btw.

this work given following simplified example:

object messagetest {   def main(args: array[string]) {     val m1 = messageimpl("foo")     val m2 = messageimpl("bar")     m1 == m2   } }  abstract class irdmessage extends ordered[irdmessage] {   val content: anyref   override def equals(obj: any): boolean = {     println("in here")     obj match{       case message: irdmessage => compareto(message) == 0       case _ => false     }   }  }  case class messageimpl(content:string) extends irdmessage{   override def compare(that:irdmessage) = 0 }

can post little more code, 1 of sample case classes? noticed if defined case class so:

case class messageimpl extends irdmessage{   var content = "foo"   override def compare(that:irdmessage) = 0 }

it not work expected.


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