scala Listの取り出し

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scala> val testList = List("aaa","bbb","ccc")
testList: List[String] = List(aaa, bbb, ccc)

scala> testList.mkString(",")
res2: String = aaa,bbb,ccc

scala> val erioList = List(List("denpa","otoko"),List("seisyun","onnna"))
erioList: List[List[String]] = List(List(denpa, otoko), List(seisyun, onnna))

scala> erioList.mkString(",")
res7: String = List(denpa, otoko),List(seisyun, onnna)

scala> erioList(0)
res8: List[String] = List(denpa, otoko)

scala> erioList(0).mkString(",")
res9: String = denpa,otoko

scala> case class Setting(name: String, data: String)
defined class Setting

scala> val denpaList = List(Setting("erio","denpa"),Setting("meme","mama"))
denpaList: List[Setting] = List(Setting(erio,denpa), Setting(meme,mama))

scala> denpaList(0).name
res15: String = erio

scala> denpaList.map(_.name)
res16: List[String] = List(erio, meme)