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scala - Is there any way to extend an object?

In scala, we cannot extend object:

object X 
object Y extends X

gives an error error: not found: type X

In my case someone has defined some functionality in an object and I need to extend it (basically add another method). What would be the easiest way to extend this object?

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As so often the correct answer depends on the actual business requirement. Extending from an object would in some sense defy the purpose of that object since it wouldn't be a singleton any longer.

What might be a solution is to extract the behavior into an abstract trait. And create objects extending that trait like so:

trait T{
    // some behavior goes here
}

object X extends T

object Y extends T {
    // additional stuff here
}

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