Override method with implicit methods. #2000
Description
Currently we are unable to override a method with an implicit method as the implicit method is not a subtype of the plain method. This is in used in the definitions of the synthetic symbols for ImplicitFunctionN but it does not work properly. I found the following two issues
- Dotty complains when we try to override a method with its equivalent implicit method.
- We are forced to implement
ImplicitFunctionN.applywithout theimplicit. Making the function class implementingImplicitFunctionNbehave as aFunctionN.
object Test { def main(args: Array[String]): Unit = { implicit val x: String = "hello" val i0: Int = new Fun0().apply val i1: Int = new Fun1().apply // ^^^^^^^^^^^^ // missing arguments for method apply in class Fun1 // follow this method with `_' if you want to treat it as a partially applied function val i2: Int = new Fun2().apply // works as expected } } class Fun0 extends ImplicitFunction1[String, Int] { def apply(implicit x: String): Int = 42 // overriding method apply in trait Function1 of type (v1: String)Int; // method apply of type (implicit x: String)Int has incompatible type } class Fun1 extends ImplicitFunction1[String, Int] { def apply(x: String): Int = 43 } class Fun2 { def apply(implicit x: String): Int = 44 } class A { def foo(x: String): Unit = () } class B extends A { def foo(implicit x: String): Unit = () // overriding method foo in trait A of type (x: String)Unit; // method foo of type (implicit x: String)Unit has incompatible type }