diff --git a/lib/HotModuleReplacementPlugin.js b/lib/HotModuleReplacementPlugin.js
index <HASH>..<HASH> 100644
--- a/lib/HotModuleReplacementPlugin.js
+++ b/lib/HotModuleReplacementPlugin.js
@@ -153,7 +153,7 @@ module.exports = class HotModuleReplacementPlugin {
 				const buf = [source];
 				buf.push("");
 				buf.push("// __webpack_hash__");
-				buf.push(`${this.requireFn}.h = () => hotCurrentHash`);
+				buf.push(this.requireFn + ".h = function() { return hotCurrentHash; };");
 				return this.asString(buf);
 			});
- Fix bug while refactoring HotModuleReplacementPlugin as suggested in PR