A given Any.Def.Tag instance for a specific type determines how this instance is converted to a String with universal ".tag" method.
Usually there is no need to create Any.Def.Tag, because it is implicitly created for standard opaque types. Reference types can mix Able.Tag instead.
Defining Any.Def.Tag is usefull for third-party existing types, one has no control over.
- Source
- Tag.scala