AngularJS 1.3 and ES6 - how to use it already today

ES6, AtScript

Next version of Angular will use AtScript - superset of ES6 (upcoming version of JavaScript). So, if you write in ES5 (current version of JavaScript), you already write in AtScript, just without all of these optional additions - annotations, types and introspections. Yes, they will stay optional, but it's nice to have them.

We can't use AtScript in existing projects yet (and Angular 2 will be ready even later than AtScript), but we already can use ES6 with AngularJS 1.3, best Angular yet (current stable branch), with all cool things ES6 going to give us. Take it now! :)

How to

Update Feb 18, 2015:

Time goes and in few weeks after publishing this article, angular-gulp generator have implemented support of ES6. I highly recommend to use it instead of generator-angular, and all ES6 support will be provided "out of the box": https://github.com/Swiip/generator-gulp-angular

I'll show you how to do it on example of the project, bootstrapped by Yeoman's generator-angular. Maybe not top-notch folders structure, but easy to start with.

Source code of project:

https://github.com/jamm/AquilamusTest

Step 1 - install modules

When we have base of project, let's add components:

Grunt will transpile ES6 to ES5 (I know I know, Gulp is our new trend, but.. next time)

npm install grunt-traceur --save-dev

PhantomJS doesn't support ES5 even, so we will run unit tests in Chrome:

npm install karma-chrome-launcher --save-dev

We need traceur runtime in app:

bower install traceur --save

That's all.

Step 2 - Structure

In structure of this project most convenient place I found for ES6 files is /app/es6 - I just copied content of 'scripts' folder here. Now I can use watch, livereload, build project and run tests. Awesome.

Step 3 - Gruntfile

Example of Gruntfile.js

And what has been changed in file, generated by generator-angular:

Diff on GutHub

We add new task, 'traceur' and add it to build, test, serve tasks. 

Step 4 - Unit tests config

Pretty simple changes:

replace PhantomJS by Chrome (it will run without taking focus, in background) and add traceur.min.js link.

Step 5 - index.html

Just add link to traceur.min.js

Enjoy ES6!

Now you can use ES6 in your AngularJS project. For example, I use ES6 classes for Services, because I like it and it works :)

Traceur will compile AtScript in the same way it compile ES6 for us in this project, so it's nice to meet Traceur already now and start use advantages of new technologies.

Additional Links

Traceur

Video - Miško Hevery - Keynote on AtScript at ng-europe 2014  (slides)

How to not minify already minified on each "grunt build" in yeoman

Long title, yeah.

Let's speed-up Grunt a little

In some of my projects I use yeoman (generator-angular), and on each "grunt build" Grunt runs minification of all JS files from the 'vendor' list (and from 'scripts' also, but it's not a problem).

It takes a long time, especially if you use a lot of external modules.

But most of them already have minified versions, so why to waste a time to minify them again?

I've made Grunt to skip minification of 'vendor' block and it decreased time of 'grunt build' execution in 5 times.

But it wasn't easy (that's why I decided to write this article).

You can't just ask usemin to skip 'vendor', but you can ignore configuration, made by usemin for uglify. To do this, add 'onlyScripts' target to your uglify task:

    uglify:        {

      onlyScripts: {

        files:   [{

          dest: '<%= yeoman.dist %>/scripts/scripts.js',

          src:  ['.tmp/concat/scripts/scripts.js']

        }]

      }

    }

Also, now uglify will not copy your vendor.js from temporary folder, so add "vendorJS" section to "copy" task:

copy:

      //...

      vendorJS: {

        expand: true,

        cwd:    '.tmp/concat/scripts/',

        dest:   '<%= yeoman.dist %>/scripts/',

        src:    'vendor.js'

      }

Then, in "build" task, set target of uglify to 'onlyScripts' and copy vendor.js:

  grunt.registerTask('build', [

    'jshint',

    'clean:dist',

    //'wiredep',

    // ...

    'useminPrepare',

    //'concurrent:dist',

    'autoprefixer',

    'concat',

    'ngAnnotate',

    'copy:dist',

    'cssmin',

    'uglify:onlyScripts',

    'copy:vendorJS',

   // ...

  ]);

About commented out lines:

 "wiredep" - this task will replace all .min.js-links (in "vendors" block) to .js-links. We don't want to allow it (otherwise our vendor.js will be huge non-minified file).

 "concurrent:dist" - when this task is commented out, Grunt works much faster on MBP with 2 cores. I don't know why. Try it, maybe it will help you too.