Explicit void

src/ol/source/Source.js

@@ -2,7 +2,7 @@
  * @module ol/source/Source
  */
 
-import {UNDEFINED} from '../functions.js';
+import {VOID} from '../functions.js';
 import BaseObject from '../Object.js';
 import {get as getProjection} from '../proj.js';
 import SourceState from '../source/State.js';
@@ -182,10 +182,10 @@ class Source extends BaseObject {
  * @param {number} hitTolerance Hit tolerance in pixels.
  * @param {Object<string, boolean>} skippedFeatureUids Skipped feature uids.
  * @param {function((module:ol/Feature|module:ol/render/Feature)): T} callback Feature callback.
- * @return {T|undefined} Callback result.
+ * @return {T|void} Callback result.
  * @template T
  */
-Source.prototype.forEachFeatureAtCoordinate = UNDEFINED;
+Source.prototype.forEachFeatureAtCoordinate = VOID;
 
 
 export default Source;

src/ol/source/Tile.js

@@ -2,7 +2,7 @@
  * @module ol/source/Tile
  */
 
-import {UNDEFINED} from '../functions.js';
+import {VOID} from '../functions.js';
 import TileCache from '../TileCache.js';
 import TileState from '../TileState.js';
 import Event from '../events/Event.js';
@@ -301,7 +301,7 @@ class TileSource extends Source {
  * @param {number} y Tile coordinate y.
  * @param {module:ol/proj/Projection} projection Projection.
  */
-TileSource.prototype.useTile = UNDEFINED;
+TileSource.prototype.useTile = VOID;
 
 
 /**

src/ol/source/Vector.js

@@ -13,7 +13,7 @@ import Event from '../events/Event.js';
 import EventType from '../events/EventType.js';
 import {containsExtent, equals} from '../extent.js';
 import {xhr} from '../featureloader.js';
-import {TRUE, UNDEFINED} from '../functions.js';
+import {TRUE, VOID} from '../functions.js';
 import {all as allStrategy} from '../loadingstrategy.js';
 import {isEmpty, getValues} from '../obj.js';
 import Source from '../source/Source.js';
@@ -176,7 +176,7 @@ class VectorSource extends Source {
      * @private
      * @type {module:ol/featureloader~FeatureLoader}
      */
-    this.loader_ = UNDEFINED;
+    this.loader_ = VOID;
 
     /**
      * @private