So siehts ganz gut aus !

node_modules/es5-ext/function/#/to-string-tokens.js

@@ -0,0 +1,17 @@
+"use strict";
+
+var validFunction = require("../valid-function");
+
+var re1 = /^\s*function[\0-')-\uffff]*\(([\0-(*-\uffff]*)\)\s*\{([\0-\uffff]*)\}\s*$/
+  , re2 = /^\s*\(?([\0-'*-\uffff]*)\)?\s*=>\s*(\{?[\0-\uffff]*\}?)\s*$/;
+
+module.exports = function () {
+	var str = String(validFunction(this)), data = str.match(re1);
+	if (!data) {
+		data = str.match(re2);
+		if (!data) throw new Error("Unrecognized string format");
+		data[1] = data[1].trim();
+		if (data[2][0] === "{") data[2] = data[2].trim().slice(1, -1);
+	}
+	return { args: data[1], body: data[2] };
+};