diff --git a/lib/LoaderOptionsPlugin.js b/lib/LoaderOptionsPlugin.js
index 8fcccedbe..21600984c 100644
--- a/lib/LoaderOptionsPlugin.js
+++ b/lib/LoaderOptionsPlugin.js
@@ -2,33 +2,35 @@
 	MIT License http://www.opensource.org/licenses/mit-license.php
 	Author Tobias Koppers @sokra
 */
-var ModuleFilenameHelpers = require("./ModuleFilenameHelpers");
+"use strict";
 
-function LoaderOptionsPlugin(options) {
-	if(typeof options !== "object") options = {};
-	if(!options.test) options.test = {
-		test: function() {
-			return true;
-		}
-	};
-	this.options = options;
-}
-module.exports = LoaderOptionsPlugin;
+const ModuleFilenameHelpers = require("./ModuleFilenameHelpers");
 
-LoaderOptionsPlugin.prototype.apply = function(compiler) {
-	var options = this.options;
-	compiler.plugin("compilation", function(compilation) {
-		compilation.plugin("normal-module-loader", function(context, module) {
-			var resource = module.resource;
-			if(!resource) return;
-			var i = resource.indexOf("?");
-			if(ModuleFilenameHelpers.matchObject(options, i < 0 ? resource : resource.substr(0, i))) {
-				Object.keys(options).filter(function(key) {
-					return ["include", "exclude", "test"].indexOf(key) < 0
-				}).forEach(function(key) {
-					context[key] = options[key];
-				});
-			}
+class LoaderOptionsPlugin {
+	constructor(options) {
+		if(typeof options !== "object") options = {};
+		if(!options.test) options.test = {
+			test: () => true
+		};
+		this.options = options;
+	}
+
+	apply(compiler) {
+		let options = this.options;
+		compiler.plugin("compilation", (compilation) => {
+			compilation.plugin("normal-module-loader", (context, module) => {
+				let resource = module.resource;
+				if(!resource) return;
+				let i = resource.indexOf("?");
+				if(ModuleFilenameHelpers.matchObject(options, i < 0 ? resource : resource.substr(0, i))) {
+					let filterSet = new Set(["include", "exclude", "test"]);
+					Object.keys(options)
+						.filter((key) => !filterSet.has(key))
+						.forEach((key) => context[key] = options[key]);
+				}
+			});
 		});
-	});
-};
+	}
+}
+
+module.exports = LoaderOptionsPlugin;