expire with scala macros

gistfile1.scala

scala> import scala.reflect.macros.blackbox.Context
import scala.reflect.macros.blackbox.Context

scala>   def expire_impl(c: Context)(): c.Expr[Unit] = {
     |     c.error(c.enclosingPosition, "has expired")
     |     c.literalUnit
     |   }
<console>:10: warning: method literalUnit in trait ExprUtils is deprecated: Use quasiquotes instead
           c.literalUnit
             ^
expire_impl: (c: scala.reflect.macros.blackbox.Context)()c.Expr[Unit]

scala> import scala.language.experimental.macros
import scala.language.experimental.macros

scala> def expire(): Unit = macro expire_impl
defined term macro expire: ()Unit

scala> expire()
<console>:12: error: has expired
              expire()