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colinmarc/gist:6575295

Created September 15, 2013 23:47
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gistfile1.scala
scala> val x = 123.asInstanceOf[String]
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at .<init>(<console>:22)
at .<clinit>(<console>)
at .<init>(<console>:11)
at .<clinit>(<console>)
at $print(<console>)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
at java.lang.Thread.run(Thread.java:724)
scala> Some(123.asInstanceOf[String])
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
at .<init>(<console>:23)
at .<clinit>(<console>)
at .<init>(<console>:11)
at .<clinit>(<console>)
at $print(<console>)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
at java.lang.Thread.run(Thread.java:724)
scala> def as[T](v : Any) = Some(v.asInstanceOf[T])
as: [T](v: Any)Some[T]
scala> as[String](123)
res64: Some[String] = Some(123)
@colinmarc
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Ooh, but:

scala> s.get
java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String
    at .<init>(<console>:25)
    at .<clinit>(<console>)
    at .<init>(<console>:11)
    at .<clinit>(<console>)
    at $print(<console>)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
    at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
    at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
    at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
    at java.lang.Thread.run(Thread.java:724)

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