Macwire，wireWith和隐式参数

Question

wireWith seems to have some issues with resolving implicit parameters.

Minimal example:

import com.softwaremill.macwire._

object A {
  def props(x: Int)(implicit y: String): A = new A(x)
}

class A(x: Int)(implicit y: String) {
   val sum: String = s"$x + $y"
}

object App {
   def main(): Unit = {
     val xVal: Int = 3
     implicit val yVal: String = "5"

     // val aInstance = wire[A] // works
     // val aInstance = A.props(xVal) // works
     val aInstance: A = wireWith(A.props _) // compile error

     println(aInstance.sum)
  }
}

App.main()

Error:

Error:(21, 33) type mismatch; found   : Int required: String
    val aInstance: A = wireWith(A.props _)
                           ^

If implicit is ommitted at yVal , it complains about missing implicit:

Error:(18, 36) could not find implicit value for parameter y: String 
    val aInstance: A = wireWith(A.props _) // compile error
                              ^

This is a simplified example though - in my production code i try to wire Actor props:

object Actor {
    def props
        (dependency: Dependency, refreshInterval: FiniteDuration @@ CacheRefreshInterval)
        (implicit ec: ExecutionContext): Props =
            Props(new Actor(dependency, refreshInterval))
}

// DI container
protected implicit def executionContext: ExecutionContext
protected lazy val dependency: Dependency = wire[Dependency]
protected lazy val refreshInterval = 2.second.taggedWith[CacheRefreshInterval]
protected lazy val actorProps: Props @@ ActorProps = actorwireWith(Actor.props _)

and get different compile error:

too many arguments for method props: (implicit ec: scala.concurrent.ExecutionContext)akka.actor.Props

I've tried making implicit parameter explicit and it worked just fine, except it's a bit against usual practice of passing execution context implicitly.

Am I doing something wrong or is it an issue in macwire?

Issue in Github: https://github.com/adamw/macwire/issues/125

Answer 1

If you were using wireWith(A.props _) as a workaround for macwire's inability to wire actors when their constructor are using implicit parameters (see macwire issue 121 ), you could switch to macwire 2.3.1 and wire your actors using wireActor[A] , wireAnonymousActor[A] or wireProps[A] . issue 121 was fixed in macwire 2.3.1.