haversine: explictly declare LongtitudeLatitude and LonLat interfaces

types/haversine/haversine-tests.ts

@@ -1,11 +1,11 @@
 import haversine = require('haversine');
 
-const start = {
+const start: haversine.CoordinateLongitudeLatitude = {
   longitude: 48.1548256,
   latitude: 11.4017529
 };
 
-const end = {
+const end: haversine.CoordinateLongitudeLatitude = {
   longitude: 52.5065133,
   latitude: 13.1445551
 };
@@ -17,12 +17,12 @@ const options: haversine.Options = {
 
 haversine(start, end, options);
 
-const startShort = {
+const startShort: haversine.CoordinateLonLat = {
   lon: 48.1548256,
   lat: 11.4017529
 };
 
-const endShort = {
+const endShort: haversine.CoordinateLonLat = {
   lon: 52.5065133,
   lat: 13.1445551
 };

types/haversine/index.d.ts

@@ -4,6 +4,16 @@
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
 declare namespace haversine {
+    interface CoordinateLongitudeLatitude {
+        longitude: number;
+        latitude: number;
+    }
+
+    interface CoordinateLonLat {
+        lon: number;
+        lat: number;
+    }
+
     type LatLonTuple = [number, number];
 
     interface GeoJSON {
@@ -12,13 +22,7 @@ declare namespace haversine {
         };
     }
 
-    type Coordinate = ({
-        longitude: number;
-        latitude: number;
-    } | {
-        lat: number;
-        lon: number;
-    } | LatLonTuple | GeoJSON);
+    type Coordinate = (CoordinateLongitudeLatitude | CoordinateLonLat | LatLonTuple | GeoJSON);
 
     interface Options {
         /**