showAsInfix

class showAsInfix(enabled: Boolean) extends StaticAnnotation

This annotation configures how Scala prints two-parameter generic types.

By default, types with symbolic names are printed infix; while types without them are printed using the regular generic type syntax.

Example of usage:

scala> class Map[T, U]
defined class Map

scala> def foo: Int Map Int = ???
foo: Map[Int,Int]

scala> @showAsInfix class Map[T, U]
defined class Map

scala> def foo: Int Map Int = ???
foo: Int Map Int
Value parameters:
enabled

whether to show this type as an infix type operator.

Source:
showAsInfix.scala
class Object
trait Matchable
class Any