object Main {
    case class MyBoolean(v: Boolean) {
        println("MyBoolean")
 
        def &&(o: MyBoolean) = v && o.v
    }
 
    case class MyLazyBoolean(v: Boolean) {
        println("MyLazyBoolean")
 
        def &&(o: => MyLazyBoolean) = v && o.v
    }
 
    def main(args: Array[String]) {
        println(MyBoolean(true) && MyBoolean(true))
        println(MyBoolean(false) && MyBoolean(true))
 
        println(MyLazyBoolean(true) && MyLazyBoolean(true))
        println(MyLazyBoolean(false) && MyLazyBoolean(true))
    }
}
 

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