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package t8013
// perverse macro to confuse Xlint
import scala.language.experimental.macros
import scala.reflect.macros.blackbox.Context
object Perverse {
implicit class Impervolator(sc: StringContext) {
def p(args: Any*): String = macro pImpl
}
// turn a nice interpolation into something that looks
// nothing like an interpolation or anything we might
// recognize, but which includes a "$id" in an apply.
def pImpl(c: Context)(args: c.Expr[Any]*): c.Expr[String] = {
import c.universe._
val macroPos = c.macroApplication.pos
val text = macroPos.source.lineToString(macroPos.line - 1) substring macroPos.column
val tt = Literal(Constant(text))
val tree = q"t8013.Perverse.pervert($tt)"
c.Expr[String](tree)
}
// identity doesn't seem very perverse in this context
//def pervert(text: String): String = text
def pervert(text: String): String = {
Console println s"Perverting [$text]"
text
}
}
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