Match parameterized type using Scala's pattern matching

Question

I have a class Operator[T: TypeTag : ClassTag] and in of it's methods, I want to use Scala's pattern matching on the parameterized type T . I know how pattern matching works and so tried the following in Scala's repl and got an error.

scala> def matchTest() = T match {
     | case x: String => "abcd"
     | case _ => null
     | }
<console>:11: error: not found: value T
       def matchTest() = T match {
                            ^

Answer 1

T is a type, not a value. You can only match on values.

You can get an implicitly[ClassTag[T]] or implicitly[TypeTag[T]] , which are values, and do matching on those.