1 files changed, 6 insertions, 3 deletions

diff --git a/eiffel-fragen/replaceability/derived2.e b/eiffel-fragen/replaceability/derived2.e
index 0622d41..7f23f15 100644
--- a/eiffel-fragen/replaceability/derived2.e
+++ b/eiffel-fragen/replaceability/derived2.e
@@ -7,7 +7,7 @@ inherit
                 end
         DERIVED
                 rename add10 as derived_add10
-                redefine myresult
+                redefine mypostcondition
                 end
 
 feature
@@ -20,8 +20,11 @@ feature
                 end
 
         -- weaken postcondition
-        myresult: INTEGER
+        mypostcondition(num: INTEGER): BOOLEAN
                 do
-                        RESULT := 20
+                        Result := false
+                        if Precursor(num) or num = 20 then
+                                Result := true
+                        end
                 end
 end