AngularJs - bind the local variable name to the remote variable name in the parent scope.

twoWayBind.js

    // Bind the local variable name to the remote variable name in the parent scope. 
    module.factory('twoWayBind', function ($parse) {
        return function (scope, local, remote) {
            // 2-way bind the model attribute
            if (angular.isUndefined(remote)) {
                remote = local;
            }
            var parentAssign = $parse(remote).assign;
            var localAssign = $parse(local).assign;
            scope.$watch(remote, function(value) {
                localAssign(scope, value);
            });
            scope.$watch(local, function(value) {
                parentAssign(scope.$parent, value);
            });
        };

    });