diff --git a/phoenix-framework/04-REST/guide/3_cat_controller.md b/phoenix-framework/04-REST/guide/3_cat_controller.md
index 75b1f27..8834231 100644
--- a/phoenix-framework/04-REST/guide/3_cat_controller.md
+++ b/phoenix-framework/04-REST/guide/3_cat_controller.md
@@ -296,7 +296,7 @@ Your controller should look like:
     case CatContext.delete_cat(cat) do # Delete the cat from the database
     {:ok, %Cat{}} ->  #If delete sucessfull, send a 200 message
             send_resp(conn, :no_content, "")
-    {:error, cs} ->   # If delete failed, notify the end user about the failure
+    {:error, _cs} ->   # If delete failed, notify the end user about the failure
         conn
         |> send_resp(400, "Something went wrong, sorry.")
     end
@@ -334,4 +334,4 @@ Start the server with an interactive session and send a GET index request to `lo
 
 The user as a parameter cats which is `#Ecto.Association.NotLoaded<association :cats is not loaded>` whilce the user_with_loaded_cats has a list of cats which are loaded. The original user has not changed as those changes are impossible in a functional programming language.
 
-Delete `require IEx; IEx.pry` to not pauze execution with every request.
\ No newline at end of file
+Delete `require IEx; IEx.pry` to not pauze execution with every request.