From f17332a0477bc44bcd76702d2e5c3b1cc4d5ac13 Mon Sep 17 00:00:00 2001
From: Daniel Barlow <dan@telent.net>
Date: Thu, 21 Nov 2024 21:53:07 +0000
Subject: [PATCH] fix low-hanging errors from elm-analyse

---
 frontend/src/Main.elm  | 24 ++++++++----------------
 frontend/src/Point.elm | 10 +++++++---
 2 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/frontend/src/Main.elm b/frontend/src/Main.elm
index e7e9d20..959b4bd 100644
--- a/frontend/src/Main.elm
+++ b/frontend/src/Main.elm
@@ -2,7 +2,7 @@ module Main exposing (view)
 
 import Browser
 import Browser.Navigation as Nav
-import Html exposing (Html, button, div, span, text, img, pre)
+import Html exposing (Html, button, div, span, text, img)
 import Html.Attributes as H exposing (src, style, width, height)
 import Html.Events exposing (onClick, on)
 import Html.Events.Extra.Pointer as Pointer
@@ -12,20 +12,17 @@ import List.Extra exposing(find)
 import Json.Decode as D
 import Http
 import Point exposing(Point, Pos ,decoder)
-import Svg exposing (Svg, svg, rect, circle, g, polyline, line)
+import Svg exposing (Svg, svg, rect, g, polyline, line)
 import Svg.Attributes as S exposing
     ( viewBox
     , preserveAspectRatio
     , transform
     , x, y
     , x1, y1 , x2, y2
-    , r, rx, ry
-    , cx, cy
     , fill
-    , points
     , stroke, strokeWidth, strokeOpacity)
-import Time exposing(Posix)
-import Url.Parser exposing (Parser, (</>), (<?>), int, map, oneOf, s, string)
+import Time --  exposing(Posix)
+import Url.Parser exposing (Parser, (<?>), int, map, s, string)
 import Url.Parser.Query as Query
 import Url exposing (Url)
 
@@ -45,12 +42,10 @@ main =
       { init = init
       , update = update
       , subscriptions = subscriptions
-      , onUrlRequest = (\ ur ->  NewUrlRequest)
-      , onUrlChange = (\ u -> UrlChanged)
+      , onUrlRequest = \ _ ->  NewUrlRequest
+      , onUrlChange = \ _ -> UrlChanged
       , view = view }
 
-
-
 -- MATHS
 
 -- Coordinates in a Mercator projection
@@ -72,9 +67,6 @@ incZoom (FineZoomLevel z) delta =
 
 type alias TileNumber = { x: Int, y: Int }
 
-type alias Lat = Float
-type alias Lng = Float
-
 -- project lat/long to co-ordinates based on pseudocode at
 -- https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#Zoom_levels
 
@@ -137,7 +129,7 @@ dragTo : Drag ->  (Int, Int) -> Drag
 dragTo d dest =
     case d of
         None -> None
-        Dragging target from to -> Dragging target from dest
+        Dragging target from _ -> Dragging target from dest
 
 dragDelta target d =
     case d of
@@ -168,7 +160,7 @@ init _ url navKey =
     in
         ((Model
               (toCoord (Pos 0 0 Nothing))
-              (FineZoomLevel (1*8)) None 0 0 Empty),
+              (FineZoomLevel (1*8)) None 0 0 Loading),
              (fetchTrack start duration))
 
 -- SUBSCRIPTIONS
diff --git a/frontend/src/Point.elm b/frontend/src/Point.elm
index dc84166..4b64459 100644
--- a/frontend/src/Point.elm
+++ b/frontend/src/Point.elm
@@ -38,10 +38,9 @@ last x xs =
         [] -> x
         (x_::xs_) -> last x_ xs_
 
-tracef x = Debug.log (String.fromFloat x) x
-
 -- divide the points into n equal time buckets and return the first
 -- point in each
+downsample : Int -> List Point -> List Point
 downsample n points =
     let
         nextpoint step prev points_ =
@@ -58,14 +57,16 @@ downsample n points =
                 in nextpoint step first rest
             [] -> []
 
+duration : List Point -> Float
 duration points =
     case points of
         (p::ps) -> (last p ps).time - p.time
         _ -> 0
 
+startTime : List Point -> Maybe Float
 startTime points =
     case points of
-        (p::ps) -> Just p.time
+        (p::_) -> Just p.time
         _ -> Nothing
 
 type Bound = Bound Pos Pos | NoBound
@@ -81,9 +82,11 @@ extendBound pos b =
            NoBound ->
                Bound pos pos
 
+bounds : List Point -> Bound
 bounds points =
     List.foldr extendBound NoBound (List.map .pos points)
 
+centre : List Point -> Pos
 centre points =
     case bounds points of
         Bound min max -> Pos
@@ -92,6 +95,7 @@ centre points =
                              Nothing
         NoBound -> Pos 0 0 Nothing
 
+subseq : List Point -> Float -> Float -> List Point
 subseq points start dur =
     case points of
         [] -> []