The current code completion feature is unable to complete semantically. For example if one types

object Test extends App {
  val xs = List("a" -> 1, "b" -> 2, "c" -> 3)
  xs.map|
}

and type CTRL+SPACE on cursor position (symbol |), content assist is activated but it doesn't show assists based on the type of the list. In this example it would be nice if something like this could be completed:

object Test extends App {
  val xs = List("a" -> 1, "b" -> 2, "c" -> 3)
  xs.map{case ([a], [b]) => |}
}

where [a] and [b] are markers to give the symbols better names and | is the cursor position after typing enter.

This could be realized in the content assist window where an option is shown to use the extractors of a type.