Chapter 1: Interfacing with a directive using isolate scope - &

HTML

<script src="https://code.angularjs.org/1.3.2/angular.min.js"></script>
<div ng-app="myApp">
    <div ng-controller="MainCtrl">
        <div iso myattr="func()"></div>
    </div>
</div>

JavaScript

angular.module('myApp', [])
.controller('MainCtrl', function ($log, $scope) {
    $scope.outerval = "mydata";
    $scope.func = function () {
        $log.log('invoked!' + this.outerval);
    };
})
.directive('iso', function () {
    return {
        scope: {
            innerval: '&myattr'
        },
        link: function(scope) {
            scope.innerval();   
            // invoked!
        }
    };
});