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scalatypeclassimplicit

Inheriting implicitNotFound messages in Scala

In Scala, thanks to the annotation.implicitNotFound annotation, we can customise the compiler's error message when an implicit is not found.

Is there a way for derived classes to somehow inherit this implicitNotFound error message? I.e., something like this:

scala> import annotation.implicitNotFound
import annotation.implicitNotFound

scala> @implicitNotFound("custom message") trait Base[T]
defined trait Base

scala> trait Derived[T] extends Base[T]
defined trait Derived

scala> implicitly[Base[Int]]
<console>:13: error: custom message 
       implicitly[Base[Int]]  // my message above, cool
                 ^

scala> implicitly[Derived[Int]]
<console>:14: error: could not find implicit value for parameter e: Derived[Int]
       implicitly[Derived[Int]]  // not my message
Solution

  • Simple answer: looks like this is not a supported feature.