extract function for gpxtpx extensions

lib/Track.hs

@@ -74,21 +74,12 @@ elToPoint c =
               >>= child
               >>= element (tpxNS "TrackPointExtension")
               >>= child
-          cadence =
-            gpxtpx
-              >>= element (tpxNS "cad")
-              >>= child
-              >>= content
-          hr =
-            gpxtpx
-              >>= element (tpxNS "hr")
-              >>= child
-              >>= content
-          power =
-            gpxtpx
-              >>= element (Name "PowerInWatts" (Just "http://www.garmin.com/xmlschemas/PowerExtension/v1") Nothing)
-              >>= child
-              >>= content
+          extn n =
+            gpxtpx >>= element n >>= child >>= content
+
+          cadence = extn (tpxNS "cad")
+          hr = extn (tpxNS "hr")
+          power = extn "{http://www.garmin.com/xmlschemas/PowerExtension/v1}PowerInWatts"
           parsedTime =
             listToMaybe ts
               >>= (Data.Time.ISO8601.parseISO8601 . Data.Text.unpack)