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import scala.language.experimental.macros
import scala.reflect.macros.blackbox.Context
object Macros {
def foo[U: Numeric](x: U) = macro foo_impl[U]
def bar[U: Numeric : Equiv, Y <% String](x: U)(implicit s: String) = macro bar_impl[U, Y]
def foo_impl[U](c: Context)(x: c.Expr[U])(numeric: c.Expr[Numeric[U]]) = {
import c.universe._
val plusOne = Apply(Select(numeric.tree, newTermName("plus")), List(x.tree, Literal(Constant(1))))
val body = Apply(Select(Ident(definitions.PredefModule), newTermName("println")), List(plusOne))
c.Expr[Unit](body)
}
def bar_impl[U, Y](c: Context)(x: c.Expr[U])(numeric: c.Expr[Numeric[U]], equiv: c.Expr[Equiv[U]], viewAsString: c.Expr[Y => String], s: c.Expr[String]) = {
import c.universe._
val plusOne = Apply(Select(numeric.tree, newTermName("plus")), List(x.tree, Literal(Constant(1))))
val plusLen = Apply(Select(numeric.tree, newTermName("plus")), List(plusOne, Select(s.tree, newTermName("length"))))
val body = Apply(Select(Ident(definitions.PredefModule), newTermName("println")), List(plusLen))
c.Expr[Unit](body)
}
}
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