https://gist.github.com/omochi/96467c674e5cf27828b09e1bb640a23a

gistfile1.txt

Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_112).
Type in expressions for evaluation. Or try :help.

scala> trait DefaultValue[A]{ def create: A }
defined trait DefaultValue

scala> implicit val intDefault = new DefaultValue[Int]{ def create = 3 }
intDefault: DefaultValue[Int] = $anon$1@68f7aae2

scala> implicit val stringDefault = new DefaultValue[String]{ def create = "po" }
stringDefault: DefaultValue[String] = $anon$1@71e7a66b

scala> def createValue[A](implicit A: DefaultValue[A]): A = A.create
createValue: [A](implicit A: DefaultValue[A])A

scala> val a = createValue[Int]
a: Int = 3

scala> val b = createValue[String]
b: String = po