diff --git a/doc/Type/Signature.pod6 b/doc/Type/Signature.pod6
index cffdb1982..e260972d8 100644
--- a/doc/Type/Signature.pod6
+++ b/doc/Type/Signature.pod6
@@ -273,6 +273,12 @@ be omitted.
     f '10', 10;
     # OUTPUT«(Int)(Str)␤»
 
+    use MONKEY;
+    augment class Str { method Date() { Date.new(self) } };
+    sub foo(Date(Str) $d) { say $d.WHAT; say $d };
+    foo "2016-12-01";
+    # OUTPUT«Date.new(2016,11,1)␤»
+
 =head2 X<Slurpy (A.K.A. Variadic) Parameters|parameter,*@;parameter,*%,slurpy argument (Signature)>
 
 A function is X<variadic> if it can take a varying number of arguments; that is,