examples/new-style-macros-example/macros/Main.scala


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package macroparadise_example.macros

import scala.meta._
import scala.collection.immutable.Seq

class Main extends scala.annotation.StaticAnnotation {
  inline def apply(defn: Any): Any = meta {
    defn match {
      case q"object $name { ..$stats }" =>
        MainMacroImpl.expand(name, stats)
      case _ =>
        abort("@main must annotate an object.")
    }
  }
}

// This is an example how we can refactor the macro implementation into a utility
// function which can be used for unit testing, see MainUnitTest.
object MainMacroImpl {
  def expand(name: Term.Name, stats: Seq[Stat]): Defn.Object = {
    val main = q"def main(args: Array[String]): Unit = { ..$stats }"
    q"object $name { $main }"
  }
}