AngularJS: Immutable constants

using IIFE

HTML

<div ng-app='App'>
    <div ng-controller="testCtrl">
        {{const1}}
        <br />
        {{const2}}
        <br />
        {{const3}}
    </div>
</div>

JavaScript

var app = angular.module('App', []);
app.constant('constants', (function () {
    var constants = {
        MY_CONSTANT: 'some value',
        MY_CONSTANT2: 'some value 2'
    };

    return function (name) {
        return constants[name];
    };
}()));

// inject them and use
app.controller('testCtrl', function ($scope, constants) {
    $scope.const1 = constants('MY_CONSTANT');
    $scope.const2 = constants('MY_CONSTANT2');
    $scope.const1 = "wow";
    $scope.const3 = constants('MY_CONSTANT')
});