remove elevation from Pos

it allows us no way to represent "elevation unknown" which is a
possibility for GPX files

lib/Track.hs

@@ -4,6 +4,7 @@ module Track (
   Track,
   Pos(..),
   pos,
+  elevation,
   parse,
   Track.length
              ) where
@@ -20,7 +21,7 @@ import Data.List as List
 import Data.Map as Map
 import Control.Exception
 
-data Pos = Pos Float Float Float deriving (Show, Eq)
+data Pos = Pos Float Float deriving (Show, Eq)
 
 
 type Power = Maybe Int
@@ -29,6 +30,7 @@ type HeartRate = Maybe Int
 
 data Point = Point {
   pos :: Pos,
+  elevation :: Maybe Float,
   time :: UTCTime,
   power :: Power,
   cadence :: Cadence,
@@ -40,15 +42,16 @@ type Track = [Point]
 mkPoint pos =
   Point
     pos
+    (Just 0)
     (UTCTime (toEnum  60631) 43200)
     (Just 0)
     (Just 0)
     (Just 0)
 
-parse :: String -> Either SomeException [Point]
 parse' str = [
   Point
-    (Pos 51.6 0 0)
+    (Pos 51.6 0)
+    (Just 0)
     (UTCTime (toEnum  60631) 43200)
     (Just 0)
     (Just 0)
@@ -63,12 +66,12 @@ elToPoint n =
       let
         lat = traceShow (getAttr "lat") (getAttr "lat")
         lon = getAttr "lon"
-      in mkPoint (Pos lat lon 0)
+      in mkPoint (Pos lat lon)
       where getAttr name =
               case (Map.lookup name attrs) of
                 Just v -> (read (Data.Text.unpack v) :: Float)
                 _ -> 0
-    _ -> mkPoint (Pos 1 2 3)
+    _ -> mkPoint (Pos 0 0)
 
 getPoints :: Cursor -> [Point]
 getPoints c =
@@ -82,6 +85,9 @@ getPoints c =
     List.map elToPoint trkpts
 
 
+-- TODO am sure we could use some amazing monad thing to reduce
+-- the amount of pattern matching here
+parse :: String -> Either SomeException [Point]
 parse str =
   case parseText def (T.pack str) of
     Right gpx ->

tests/UnitTest.hs

@@ -24,7 +24,7 @@ test2 = TestCase $
           Right (p:ps) ->
             assertEqual "matches lat/lon"
              (Track.pos p)
-             (Track.Pos 51.0 (-0.1) 0.0)
+             (Track.Pos 51.0 (-0.1))
 
 tests :: Test
 tests = TestList [