From d5741d38391cbca50a58365eeb0cf68df8848cbc Mon Sep 17 00:00:00 2001
From: hasufell <hasufell@hasufell.de>
Date: Fri, 14 Nov 2014 22:58:21 +0100
Subject: [PATCH] PARSER: use 'Either' from Prelude instead of custom
 QuadOrOrient

---
 Graphics/Diagram/Plotter.hs | 16 ++++++++--------
 Parser/PathParser.hs        | 29 +++++++++++------------------
 2 files changed, 19 insertions(+), 26 deletions(-)

diff --git a/Graphics/Diagram/Plotter.hs b/Graphics/Diagram/Plotter.hs
index 2693d06..7e49683 100644
--- a/Graphics/Diagram/Plotter.hs
+++ b/Graphics/Diagram/Plotter.hs
@@ -197,11 +197,11 @@ quadPathSquare = Diag f
         # moveTo (p2 ((xmax + xmin) / 2,(ymax + ymin) / 2)) # lw thin # lc red)
         (getSquare (stringToQuads (pQt p)) (qt, []))
       where
-        getSquare :: [QuadOrOrient] -> Zipper PT -> Square
+        getSquare :: [Either Quad Orient] -> Zipper PT -> Square
         getSquare [] z = getSquareByZipper (dX p, dY p) z
         getSquare (q:qs) z = case q of
-          Orient x -> getSquare qs (fromMaybe z (findNeighbor x z))
-          Quad x -> getSquare qs (fromMaybe z (goQuad x z))
+          Right x -> getSquare qs (fromMaybe z (findNeighbor x z))
+          Left x  -> getSquare qs (fromMaybe z (goQuad x z))
         qt :: QuadTree PT
         qt = quadTree vtf (dX p, dY p)
         vtf :: [PT]
@@ -218,13 +218,13 @@ gifQuadPath = GifDiag f
         # moveTo (p2 ((xmax + xmin) / 2,(ymax + ymin) / 2)) # lw thick # lc col)
         <$> (getSquares (stringToQuads (pQt p)) (qt, []))
       where
-        getSquares :: [QuadOrOrient] -> Zipper PT -> [Square]
+        getSquares :: [Either Quad Orient] -> Zipper PT -> [Square]
         getSquares [] z = [getSquareByZipper (dX p, dY p) z]
         getSquares (q:qs) z = case q of
-          Orient x -> getSquareByZipper (dX p, dY p) z :
-                      getSquares qs (fromMaybe z (findNeighbor x z))
-          Quad x -> getSquareByZipper (dX p, dY p) z :
-                    getSquares qs (fromMaybe z (goQuad x z))
+          Right x -> getSquareByZipper (dX p, dY p) z :
+                       getSquares qs (fromMaybe z (findNeighbor x z))
+          Left x  -> getSquareByZipper (dX p, dY p) z :
+                       getSquares qs (fromMaybe z (goQuad x z))
         qt :: QuadTree PT
         qt = quadTree vtf (dX p, dY p)
         vtf :: [PT]
diff --git a/Parser/PathParser.hs b/Parser/PathParser.hs
index f844653..9986c98 100644
--- a/Parser/PathParser.hs
+++ b/Parser/PathParser.hs
@@ -7,16 +7,9 @@ import Parser.Core
 import Algorithms.RangeSearch.Core (Quad(NW, NE, SW, SE), Orient(North, South, West, East))
 
 
--- |Can either be an Orientation or a Quad, corresponding to the
--- Algorithms.RangeSearch module.
-data QuadOrOrient = Orient Orient
-                  | Quad Quad
-  deriving (Show)
-
-
 -- |Parse a string such as "ne, n, sw, e" into
 -- [Quad NE, Orient North, Quad SW, Orient East].
-stringToQuads :: String -> [QuadOrOrient]
+stringToQuads :: String -> [Either Quad Orient]
 stringToQuads str = case runParser parsePath str of
   Nothing -> []
   Just xs -> fst xs
@@ -28,19 +21,19 @@ stringToQuads str = case runParser parsePath str of
 
 -- |Parses a string that represents a single squad into the
 -- QuadOrOrient ADT.
-parseQuad :: Parser QuadOrOrient
+parseQuad :: Parser (Either Quad Orient)
 parseQuad =
-  const (Quad NW) <$> (string "nw" <|> string "NW")
-    <|> const (Quad NE) <$> (string "ne" <|> string "NE")
-    <|> const (Quad SW) <$> (string "sw" <|> string "SW")
-    <|> const (Quad SE) <$> (string "se" <|> string "SE")
+  const (Left NW) <$> (string "nw" <|> string "NW")
+    <|> const (Left NE) <$> (string "ne" <|> string "NE")
+    <|> const (Left SW) <$> (string "sw" <|> string "SW")
+    <|> const (Left SE) <$> (string "se" <|> string "SE")
 
 
 -- |Parses a string that represents a single Orientation into the
 -- QuadOrOrient ADT.
-parseOrient :: Parser QuadOrOrient
+parseOrient :: Parser (Either Quad Orient)
 parseOrient =
-  const (Orient North) <$> (string "n" <|> string "N")
-    <|> const (Orient South) <$> (string "s" <|> string "S")
-    <|> const (Orient West) <$> (string "w" <|> string "W")
-    <|> const (Orient East) <$> (string "e" <|> string "E")
+  const (Right North) <$> (string "n" <|> string "N")
+    <|> const (Right South) <$> (string "s" <|> string "S")
+    <|> const (Right West) <$> (string "w" <|> string "W")
+    <|> const (Right East) <$> (string "e" <|> string "E")