Merge pull request #2057 from paulp/pr/revert-6355

SI-6355, weakend implementation restriction on applyDynamic.

1 files changed, 5 insertions, 6 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
index 7c60ce275a..60a73036f8 100644
--- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
@@ -136,9 +136,8 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
 
       // Check for doomed attempt to overload applyDynamic
       if (clazz isSubClass DynamicClass) {
-        clazz.info member nme.applyDynamic match {
-          case sym if sym.isOverloaded => unit.error(sym.pos, "implementation restriction: applyDynamic cannot be overloaded")
-          case _                       =>
+        for ((_, m1 :: m2 :: _) <- (clazz.info member nme.applyDynamic).alternatives groupBy (_.typeParams.length)) {
+          unit.error(m1.pos, "implementation restriction: applyDynamic cannot be overloaded except by methods with different numbers of type parameters, e.g. applyDynamic[T1](method: String)(arg: T1) and applyDynamic[T1, T2](method: String)(arg1: T1, arg2: T2)")
         }
       }
 
@@ -1237,12 +1236,12 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
      */
     private def checkMigration(sym: Symbol, pos: Position) = {
       if (sym.hasMigrationAnnotation) {
-        val changed = try 
+        val changed = try
           settings.Xmigration.value < ScalaVersion(sym.migrationVersion.get)
         catch {
-          case e : NumberFormatException => 
+          case e : NumberFormatException =>
             unit.warning(pos, s"${sym.fullLocationString} has an unparsable version number: ${e.getMessage()}")
-            // if we can't parse the format on the migration annotation just conservatively assume it changed         
+            // if we can't parse the format on the migration annotation just conservatively assume it changed
             true
         }
         if (changed)