Could not find implicit value for parameter flash

I'm trying to port some code from Play Framework Java to Play Framework Scala but I'm having some issues with porting a tag.

The tag in question in the Java version checks the contents of the Flash scope and creates notifications to the user according to its values (error, success, etc).

I tried to create a Scala view (flag.scala.html):

@()(implicit flash:play.mvc.Scope.Flash)

@if(flash.get("error")) {
    <p style="color:#c00">
        @flash.get("error")
    </p>
}

Which I call from main.scala.html via:

@views.Application.html.flag()

The error I get is:

The file {module:.}/tmp/generated/views.html.main.scala could not be compiled. Error raised is : could not find implicit value for parameter flash: play.mvc.Scope.Flash

The call to the new tag is correct, as if I replace the content by some String that's shown in the browser.

I'm sure it's something stupid but I got stuck. Any suggestion?