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import scala.reflect.runtime.universe._
import scala.reflect.macros.Context
object Impls1 {
def foo[U: c.WeakTypeTag](c: Context)(x: c.Expr[U]) = {
import c.universe._
val U = implicitly[c.WeakTypeTag[U]]
val body = Apply(Select(Ident(definitions.PredefModule), TermName("println")), List(Literal(Constant(U.toString))))
c.Expr[Unit](body)
}
}
object Impls2 {
def foo[T: c.WeakTypeTag, U: c.WeakTypeTag](c: Context)(x: c.Expr[U]) = {
import c.universe._
val T = implicitly[c.WeakTypeTag[T]]
val U = implicitly[c.WeakTypeTag[U]]
val body = Apply(Select(Ident(definitions.PredefModule), TermName("println")), List(Literal(Constant(T.toString + " " + U.toString))))
c.Expr[Unit](body)
}
}
object Impls345 {
def foo[T, U: c.WeakTypeTag, V](c: Context)(implicit T: c.WeakTypeTag[T], V: c.WeakTypeTag[V]): c.Expr[Unit] = {
import c.universe._
c.Expr(Block(List(
Apply(Select(Ident(definitions.PredefModule), TermName("println")), List(Literal(Constant(T.toString)))),
Apply(Select(Ident(definitions.PredefModule), TermName("println")), List(Literal(Constant(implicitly[c.WeakTypeTag[U]].toString)))),
Apply(Select(Ident(definitions.PredefModule), TermName("println")), List(Literal(Constant(V.toString))))),
Literal(Constant(()))))
}
}
object Macros4 {
class D[T] {
class C[U] {
def foo[V] = macro Impls345.foo[T, U, V]
}
}
}
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