diff options
| -rw-r--r-- | src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala b/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala index eb96f87e0e..b373b3d0de 100644 --- a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala +++ b/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala @@ -232,9 +232,13 @@ abstract class CPSAnnotationChecker extends CPSUtils with Modes { } else tree } - // only adapt type if this return will - // (a) be removed (in tail position and method's result type (pt) is cps type), or - // (b) cause an error + /** Returns an adapted type for a return expression if the method's result type (pt) is a CPS type. + * Otherwise, it returns the `default` type (`typedReturn` passes `NothingClass.tpe`). + * + * A return expression in a method that has a CPS result type is an error unless the return + * is in tail position. Therefore, we are making sure that only the types of return expressions + * are adapted which will either be removed, or lead to an error. + */ override def adaptTypeOfReturn(tree: Tree, pt: Type, default: => Type): Type = { // only adapt if method's result type (pt) is cps type val annots = cpsParamAnnotation(pt) |