test/files/pos/t10066.scala


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package dynamicrash
 
import scala.language.dynamics
 
class Config
 
trait Extractor[A] {
  def extract(config: Config, name: String): A
}
 
object Extractor {
  // this has "implicit", unlike the corresponding neg test
  implicit val stringExtractor = new Extractor[String] {
    override def extract(config: Config, name: String): String = ???
  }
}
 
class Workspace extends Dynamic {
  val config: Config = new Config
 
  def selectDynamic[A](name: String)(implicit extractor: Extractor[A]): A =
    extractor.extract(config, name)
}
 
object Main {
  val storage = new Workspace
 
  // this line works fine
  // val a = storage.foo
 
  // this line crashes the compiler ("head of empty list")
  // in ContextErrors$InferencerContextErrors$InferErrorGen$.NotWithinBoundsErrorMessage
  println(storage.foo[String])
 
  // this line crashes the compiler in different way ("unknown type")
  // in the backend, warning: an unexpected type representation reached the compiler backend while compiling Test.scala: <error>
  println(storage.foo)
}