From 01fa10fefb0b577210881f53490e4ff3a6c0212c Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Mon, 14 Dec 2020 11:21:42 +0000
Subject: [PATCH] Fix when "Yes." is displayed.

It is now displayed whenever a solution is found but no variable assignments is
printed.
---
 src/Propa/Prolog/Display.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Propa/Prolog/Display.hs b/src/Propa/Prolog/Display.hs
index 433dfc7..d4e1eeb 100644
--- a/src/Propa/Prolog/Display.hs
+++ b/src/Propa/Prolog/Display.hs
@@ -62,9 +62,9 @@ displayDefs :: [Def T.Text] -> T.Text
 displayDefs = T.intercalate "\n" . map displayDef
 
 displayResult :: Map.Map T.Text (Term T.Text) -> T.Text
-displayResult m | Map.null m = "Yes."
 displayResult m
-  = T.intercalate "\n"
-  $ map (\(k, v) -> k <> " = " <> displayTerm v)
-  $ filter (\(k, v) -> v /= TVar k)
-  $ Map.assocs m
+  | null termsToDisplay = "Yes."
+  | otherwise           = T.intercalate "\n" termsAsStrings
+  where
+    termsToDisplay = filter (\(k, v) -> v /= TVar k) $ Map.assocs m
+    termsAsStrings = map (\(k, v) -> k <> " = " <> displayTerm v) termsToDisplay