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import scala.language.experimental.macros
import scala.reflect.macros.whitebox.Context
object Macros {
def id[A]: A = null.asInstanceOf[A]
def foo: Any = macro impl
def impl(c: Context): c.Tree = {
import c.universe._
import Flag._
lazy val tpe = TypeTree(typeOf[Int])
/* If we used this line instead, it would work! */
// lazy val tpe = tq"Int"
lazy val param: ValDef = {
val p1 = q"val a: ${tpe.duplicate} = Macros.id[${tpe.duplicate}]"
ValDef(Modifiers(DEFAULTPARAM), p1.name, p1.tpt, p1.rhs)
}
q"""
class C { def f($param) = a }
println(new C().f())
"""
}
}
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