ZeroC Ice "checked casts" in Scala

Posted by Alexey Romanov on Stack Overflow See other posts from Stack Overflow or by Alexey Romanov
Published on 2010-04-22T16:48:53Z Indexed on 2010/04/22 16:53 UTC
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scala

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types

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ice

ZeroC Ice for Java translates every Slice interface Simple into (among other things) a proxy interface SimplePrx and a proxy SimplePrxHelper. If I have an ObjectPrx (the base interface for all proxies), I can check whether it actually has interface Simple by using a static method on SimplePrxHelper:

val obj : Ice.ObjectPrx = ...;        // Get a proxy from somewhere...

val simple : SimplePrx = SimplePrxHelper.checkedCast(obj);
if (simple != null)
    // Object supports the Simple interface...
else
    // Object is not of type Simple...

I wanted to write a method castTo so that I could replace the second line with

val simple = castTo[SimplePrx](obj)

or

val simple = castTo[SimplePrxHelper](obj)

So far as I can see, Scala's type system is not expressive enough to allow me to define castTo. Is this correct?

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