diff --git a/package.json b/package.json
index 16b5b83..8950d33 100644
--- a/package.json
+++ b/package.json
@@ -12,7 +12,7 @@
 "clean": "rimraf dist && mkdirp dist",
 "rollup:cjs": "rollup -c rollup.config.js -m -f cjs -n $npm_package_amdName $npm_package_jsnext_main -o $npm_package_main",
 "rollup:umd": "rollup -c rollup.config.js -m -f umd -n $npm_package_amdName $npm_package_jsnext_main -o $npm_package_umd_main",
- "minify:cjs": "uglifyjs $npm_package_main -cm toplevel -o $npm_package_main -p relative --in-source-map ${npm_package_main}.map --source-map ${npm_package_main}.map",
+ "minify:cjs": "uglifyjs $npm_package_main -cm toplevel --reserved mitt -o $npm_package_main -p relative --in-source-map ${npm_package_main}.map --source-map ${npm_package_main}.map",
 "minify:umd": "uglifyjs $npm_package_umd_main -cm -o $npm_package_umd_main -p relative --in-source-map ${npm_package_umd_main}.map --source-map ${npm_package_umd_main}.map",
 "docs": "documentation readme src/index.js --section API -q",
 "size": "echo \"Gzipped Size: $(strip-json-comments --no-whitespace $npm_package_main | gzip-size | pretty-bytes)\"",
@@ -48,7 +48,11 @@
 "es6": true
 },
 "globals": {
- "expect": true
+ "expect": true,
+ "module": true
+ },
+ "rules": {
+ "no-empty": 0
 }
 },
 "devDependencies": {
diff --git a/src/index.js b/src/index.js
index 36b25f1..b833e3f 100644
--- a/src/index.js
+++ b/src/index.js
@@ -2,15 +2,9 @@
 *	@name mitt
 *	@returns {Mitt}
 */
-export default function mitt(all) {
+function mitt() {
 	// Arrays of event handlers, keyed by type
-	all = all || {};
-
-	// Get or create a named handler list
-	function list(type) {
-		let t = type.toLowerCase();
-		return all[t] || (all[t] = []);
-	}
+	let all = {};
 
 	return {
 
@@ -20,7 +14,7 @@ export default function mitt(all) {
 		 *	@memberof mitt
 		 */
 		on(type, handler) {
-			list(type).push(handler);
+			(all[type = type.toLowerCase()] || (all[type] = [])).push(handler);
 		},
 
 		/** Remove an event handler for the given type.
@@ -29,9 +23,8 @@ export default function mitt(all) {
 		 *	@memberof mitt
 		 */
 		off(type, handler) {
-			let e = list(type),
-				i = e.indexOf(handler);
-			if (~i) e.splice(i, 1);
+			let e = all[type = type.toLowerCase()] || (all[type] = []);
+			e.splice(e.indexOf(handler)>>>0, 1);
 		},
 
 		/** Invoke all handlers for the given type.
@@ -41,7 +34,9 @@ export default function mitt(all) {
 		 *	@memberof mitt
 		 */
 		emit(type, event) {
-			list('*').concat(list(type)).forEach( f => { f(event); });
+			(all[type = type.toLowerCase()] || []).map( f => { f(event); });
+			(all['*'] || []).map( f => { f(type, event); });
 		}
 	};
 }
+try { module.exports = mitt; }catch(e){}
</div><div class="naked_ctrl">
<form action="/index.cgi/contrast" method="get" name="gate">
<p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://GITHUB.COM/developit/mitt/compare/main...smaller.diff">(-&gt;オリジナル)</a>
/ <label>アドレス: <input type="text" name="naked_post_url" value="https://GITHUB.COM/developit/mitt/compare/main...smaller.diff" size="22" /></label> <label>モード: <select name="naked_post_mode">
<option value="default">デフォルト</option>
<option value="speech">音声ブラウザ</option>
<option value="ruby">ルビ付き</option>
<option value="contrast" selected="selected">配色反転</option>
<option value="larger-text">文字拡大</option>
<option value="mobile">モバイル</option>
</select>
<input type="submit" value="表示" />
</p>
</form>
</div>