diff --git a/src/sphinx/Extending/Settings-Core.rst b/src/sphinx/Extending/Settings-Core.rst
index 55aac166c..2d5e75fa2 100644
--- a/src/sphinx/Extending/Settings-Core.rst
+++ b/src/sphinx/Extending/Settings-Core.rst
@@ -118,7 +118,7 @@ for details.
           // Define some settings
        val mySettings: Seq[Setting[_]] = Seq(
           setting( a3, value( 3 ) ),
-          setting( b4, app(a4 :^: KNil) { case av :+: HNil => av * 3 } ),
+          setting( b4, map(a4)(_ * 3)),
           update(a5)(_ + 1)
        )