FizzBuzz.scala

/**
 * Created by kamiya on 2015/02/24.
 * libraryDependencies += "org.scala-lang" % "scala-compiler" % scalaVersion.value
 */
import scala.reflect.runtime.currentMirror
import scala.tools.reflect.ToolBox

object FizzBuzz {
  class TraitCreator(name:String,const:String,superClass:String = "AnyRef") {
    def make(n:Int = 1) : Stream[String] =
      s"trait $name$n extends $superClass { $const }" #:: make(n + 1)
    def get(n:Int = 1) : Stream[String] = s"$name$n" #:: get(n + 1)

  }
  class MemorizeTraitCreator(name:String,const:String,superClass:String = "AnyRef") extends TraitCreator(name,const,superClass) {
    var currentN = 1
    def get : String = {
      val g = super.get(currentN).head
      currentN += 1
      g
    }
    def make : String = {
      super.make(1).take(currentN - 1).mkString("",";",";")
    }
  }
  def main(args:Array[String]) : Unit = {
    val n = new MemorizeTraitCreator("N","println(n) ; incr","FizzBuzz")
    val f =new  MemorizeTraitCreator("F","println(\"Fizz\") ; incr","FizzBuzz")
    val b = new MemorizeTraitCreator("B","println(\"Buzz\") ; incr","FizzBuzz")
    val fb = new MemorizeTraitCreator("FB","println(\"FizzBuzz\") ; incr","FizzBuzz")
    def fbgen(i:Int) = i % 15 match {
      case 0 => fb.get
      case x if x % 5 == 0 => b.get
      case x if x % 3 == 0 => f.get
      case _ => n.get
    }
    val g = "new Hoge(1)" + (1 to 100).flatMap(i => " with " + fbgen(i)).mkString
    val d = "trait FizzBuzz extends AnyRef { var n:Int; def incr = n +=1 } ; class Hoge(var n:Int = 1) {} ; " + n.make + f.make + b.make +  fb.make
    val tb = currentMirror.mkToolBox()
    println(tb.eval(tb.parse(d + g)))
  }
}