JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.angularjs.org/1.0.1/angular-1.0.1.min.js"></script>
<div ng-app="Foo">
    <two order-by="test">test</two>
</div>

JavaScript

var app = angular.module("Foo", []);

app.directive("two", function () {
    return {
        scope: {
            orderBy: '@'
        },
        restrict: 'E',
        transclude: true,
        controller: function ($scope, $element, $attrs) {
            console.log($scope.orderBy); // is undefined, why?   
        },
        template: '<div></div>',
        replace: true
    };
});