From b68222dab7a766ede897ba9bdc68f262e2194e3d Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Sat, 26 May 2018 13:15:27 -0700
Subject: [PATCH] Prettify some code.

---
 Go/Game.elm |  4 +++-
 Go/Util.elm | 13 ++++++++++---
 Go/View.elm |  5 +++--
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/Go/Game.elm b/Go/Game.elm
index 1dc65f0..5328cb7 100644
--- a/Go/Game.elm
+++ b/Go/Game.elm
@@ -1,6 +1,8 @@
 module Go.Game exposing (verify)
 import Go.Types exposing (..)
 import Go.Util exposing (lookup)
+import List exposing (foldl)
+import Maybe exposing (andThen)
 
 -- Make sure it's our turn to play.
 verifyTurn : Model -> Cell -> Maybe Cell
@@ -24,7 +26,7 @@ verifyBounds model ((x, y), c) = if x >= 0 && x < model.sessionSize && y >= 0 &&
 
 -- Verify a cell placemenet using a list of verification functions.
 verifyAll : Cell -> List (Model -> Cell -> Maybe Cell) -> Model -> Maybe Cell
-verifyAll cell funcs model = List.foldl (\a b -> Maybe.andThen (a model) b) (Just cell) funcs
+verifyAll cell funcs model = List.foldl (\a b -> andThen (a model) b) (Just cell) funcs
 
 -- Make sure that a move to the given cell can be made.
 verify : Cell -> Model -> Maybe Cell
diff --git a/Go/Util.elm b/Go/Util.elm
index d9d9c81..44cccc2 100644
--- a/Go/Util.elm
+++ b/Go/Util.elm
@@ -1,27 +1,34 @@
 module Go.Util exposing (..)
 import Go.Types exposing (..)
+import List exposing (map, head, filter, range)
+import Tuple exposing (second, first)
 
+-- Creates a pair of two elements.
 pair : a -> b -> (a, b)
 pair a1 a2 = (a1, a2)
 
 -- Search for a value in a list of key-value pairs.
 lookup : a -> List (a, b) -> Maybe b
-lookup val list = Maybe.map Tuple.second (List.head (List.filter (\(a, _) -> a == val) list))
+lookup val list = Maybe.map second 
+    <| head 
+    <| filter ((\a -> a == val) << first) list
 
 -- Computes all possible indices on a board of size n.
 allIndices : Int -> List Index
 allIndices n = 
     let
-        vals = List.range 0 (n - 1)
-        pairs = \xs i -> List.map (\x -> (i, x)) xs
+        vals = range 0 (n - 1)
+        pairs = \xs i -> map (pair i) xs
     in
         List.concatMap (pairs vals) vals
 
 
+-- Computes a zip of two lists.
 zip : List a -> List b -> List (a, b)
 zip xs ys = case (xs, ys) of
     (x::xb, y::yb) -> (x, y) :: (zip xb yb)
     _ -> []
 
+-- Swaps the arguments of a two-argument function.
 swap : (a -> b -> c) -> b -> a -> c
 swap f vb va = f va vb
diff --git a/Go/View.elm b/Go/View.elm
index 2e75c1a..f10870d 100644
--- a/Go/View.elm
+++ b/Go/View.elm
@@ -4,6 +4,7 @@ import Go.Types exposing (..)
 import Html exposing (Html, div, text, p)
 import Html.Attributes exposing (class, classList)
 import Html.Events exposing (onClick)
+import List exposing (map)
 
 renderIndex : (Index, Maybe Color) -> Html Msg
 renderIndex (index, color) = 
@@ -21,6 +22,6 @@ renderIndex (index, color) =
 renderBoard : Int -> Board -> Html Msg
 renderBoard size board = 
     let 
-        cells = List.map (\i -> (lookup i board) |> (pair i)) <| allIndices size
+        cells = map (\i -> (i, lookup i board)) <| allIndices size
     in
-        div [ class "board" ] <| List.map renderIndex cells
+        div [ class "board" ] <| map renderIndex cells