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import scala.language.experimental.macros
import scala.reflect.macros.blackbox.Context
trait LegacyLiftable[T] {
def apply(universe: scala.reflect.api.Universe, value: T): universe.Tree
}
object LegacyLiftable {
implicit def liftCaseClass[T <: Product]: LegacyLiftable[T] = macro liftCaseClassImpl[T]
def liftCaseClassImpl[T: c.WeakTypeTag](c: Context): c.Expr[LegacyLiftable[T]] = {
import c.universe._
val tpe = weakTypeOf[T]
if (!tpe.typeSymbol.asClass.isCaseClass) c.abort(c.enclosingPosition, "denied")
val p = List(q"Literal(Constant(1))")
c.Expr[LegacyLiftable[T]] { q"""
new LegacyLiftable[$tpe] {
def apply(universe: scala.reflect.api.Universe, value: $tpe): universe.Tree = {
import universe._
Apply(Select(Ident(TermName("C")), TermName("apply")), List(..$p))
}
}
""" }
}
}
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