diff --git a/lib/ace/mode/coffee_highlight_rules.js b/lib/ace/mode/coffee_highlight_rules.js
index 2da2c1d9..98253f49 100644
--- a/lib/ace/mode/coffee_highlight_rules.js
+++ b/lib/ace/mode/coffee_highlight_rules.js
@@ -92,7 +92,7 @@ define(function(require, exports, module) {
         var functionRe = {
             "({args})->": {
                 token: ["paren.lparen", "text", "paren.lparen", "text", "variable.parameter", "text", "paren.rparen", "text", "paren.rparen", "text", "storage.type"],
-                regex: "(\\()(\\s*)(\\{)(\\s*)(" + [headRe, headRe + "[$\\w\\s,\\x7f-\\uffff]*"].join("|") + ")(\\s*)(\\})(\\s*)(\\))(\\s*)([\\-=]>)"
+                regex: "(\\()(\\s*)(\\{)(\\s*)(" + headRe + "[$\\w\\s,\\x7f-\\uffff]*" + ")(\\s*)(\\})(\\s*)(\\))(\\s*)([\\-=]>)"
             },
             "({})->": {
                 token: ["paren.lparen", "text", "paren.lparen", "text", "paren.rparen", "text", "paren.rparen", "text", "storage.type"],