Convert Option[Object] to Option[Int] Implicitly

Posted by wheaties on Stack Overflow See other posts from Stack Overflow or by wheaties
Published on 2010-03-20T01:38:03Z Indexed on 2010/03/20 1:41 UTC
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scala

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implicit

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type-conversion

I'm working with legacy Java code which returns java.lang.object. I'm passing it into a function and I'd like to do some implicit conversions as such:

implicit def asInt( _in:Option[Object] ) = _in asInstanceOf[ Option[Int] ]
implicit def asDouble( _in:Option[Object] = _in asInstanceOf[ Option[Double] ]

private def parseEntry( _name:String, _items:Map[String,Object] ) = _name match{
    case docName.m_Constants =>
        new Constants( _items get( Constants m_Epsilon ), _items get( Constant m_Rho ),
                       _items get( Constants m_N ) )

Technically it goes on but I keep getting the same errors: expected Int, Option[Object] found.

How have I done my implicits wrong? I was hoping it would do the transformation for me instead of me having to write "asInstanceOf" each and every time.

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