unreachable code? and REPL crash

please ignore the dumb question about unreachable code. still, the REPL crashes...

Ittay Dror wrote:
>
>
> saving the code below and loading it in the REPL:
>
> scala> :load c:\temp\loopwhile.scala
> Loading c:\temp\loopwhile.scala...
> doBeforeBeginOnly: Unit
> :18: error: unreachable code
> case 'end => ended = true
>
>
> loading it again:
>
> scala> :load c:\temp\loopwhile.scala
> Loading c:\temp\loopwhile.scala...
> doBeforeBeginOnly: Unit
> Exception in thread "main" java.lang.NullPointerException
> at scala.tools.nsc.Global$Run.compileLate(Global.scala:826)
> at scala.tools.nsc.symtab.SymbolLoaders$SourcefileLoader.doComplete(SymbolLoaders.scala:265)
> at scala.tools.nsc.symtab.SymbolLoaders$SymbolLoader.complete(SymbolLoaders.scala:61)
> at scala.tools.nsc.symtab.SymbolLoaders$SymbolLoader.complete(SymbolLoaders.scala:35)
> at scala.tools.nsc.symtab.Symbols$Symbol.info(Symbols.scala:743)
> at scala.tools.nsc.transform.SpecializeTypes$$anon$5.apply(SpecializeTypes.scala:196)
> at scala.tools.nsc.transform.SpecializeTypes$$anon$5.apply(SpecializeTypes.scala:188)
> at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:206)
> at scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:206)
> at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:61)
> at scala.collection.immutable.List.foreach(List.scala:45)
> at scala.collection.TraversableLike$class.map(TraversableLike.scala:206)
> at scala.collection.immutable.List.map(List.scala:45)
>
>
> and the REPL crashes
>
>
> why isn't the variable reachable?
>
>
> regards,
>
> Ittay
>
>
> code:
>
> import scala.actors.Actor._
>
> def doBeforeBeginOnly = println("before")
>
> val a = actor {
> loop {
> doBeforeBeginOnly
> react {
> case 'begin => println("begin")
> var ended = false
> loopWhile(!ended) {
> react {
> case msg => println(msg)
> case 'end => ended = true
> }
> }
> }
> }
> }
>
>
>
>