FromTrait - https://rust-lang-ja.github.io/the-rust-programming-language-ja/1.6/book/error-handling.html

From.scala

trait From[T, S] {
  def from(t: T): S
}

object From {
  def from[T, S](t: T)(implicit F: From[T, S]): S = F.from(t)
}

implicit val fromIntToString = new From[Int, String] {
  def from(i: Int): String = i.toString
}

implicit val fromDoubleToString = new From[Double, String] {
  def from(d: Double): String = d.toString
}

implicit val fromBooleanToString = new From[Boolean, String] {
  def from(b: Boolean): String = b.toString
}


val str1: String = From.from(1)
val str2: String = From.from(true)
val str3: String = From.from(4.2)