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@wheaties
Forked from frankleonrose/IsNotFuture
Last active August 29, 2015 14:08
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trait IsNotFuture[+F]
object IsNotFuture{
def apply[F](implicit isf: IsNotFuture[F]) = isf
implicit def mkFuture[A] = new IsNotFuture[Future[A]] {}
implicit object isf extends IsNotFuture[Any] {}
}
//No need for a dependent type. All you need is the implicit ambiguity.
def inSession[T](fn: (Session) => T)(implicit isNotFuture: IsNotFuture[T]): T = {
db withSession fn
}
// Compiler fails as desired
inSession { session => Future(1) }
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