--- title: "This week's JavaScript news, issue 190" publication: "JavaScript Weekly" issue: 190 published_at: "2014-07-18" canonical_url: "https://javascriptweekly.com/issues/190" --- This week's JavaScript news, issue 190 jQuery source surprises, Angular 'scope creep', in-depth famo.us tutorial + more — [Read this e-mail on the Web](http://javascriptweekly.com/issues/190) JavaScript WeeklyIssue 190 — July 18, 2014[18 Surprises From Reading jQuery's Source Code](http://quickleft.com/blog/18-surprises-from-reading-jquery-s-source-code) David Aragon decided to read the source code to jQuery and found a variety of things he hadn’t expected. In the comments, however, Dave Methvin notes that you need to be careful as undocumented features can change without notice. David Aragon [Leverage Scope Creep: An In-depth Tutorial on Angular.js Scope](http://modernweb.com/2014/07/14/leverage-scope-creep-depth-tutorial-angular-js-scope/) Jonathan Creamer presents a tutorial on mastering ‘Scope’ within Angular.js, from $rootScope down through scope within Controllers and Directives. ModernWeb [Create High Performance Mobile UIs with Famo.us](http://www.ibm.com/developerworks/library/wa-famous/index.html) With the Famo.us platform, mobile web UIs written in JavaScript can be as compelling as native-code implementations. Work through this article’s examples to find out how Famo.us helps you easily create a high-performance user experience in your mobile apps. IBM developerWorks [![Rackspace\](http://s3.amazonaws.com/nlga/uploads/item/image/25156/t.jpg)](http://www.rackspace.com/knowledge_center/sites/default/files/whitepaper_pdf/RS_Making%20Mobile%20Seamless_whitepaper_web.pdf?cm_mmc=managed-_-cloud-_-contentnam-_-javascript-seamless)[How to Make Mobile Seamless (free PDF whitepaper)](http://www.rackspace.com/knowledge_center/sites/default/files/whitepaper_pdf/RS_Making%20Mobile%20Seamless_whitepaper_web.pdf?cm_mmc=managed-_-cloud-_-contentnam-_-javascript-seamless) Even with spotty cellular network connections, mobile consumers still expect their apps to work seamlessly. Download [this whitepaper](http://www.rackspace.com/knowledge_center/sites/default/files/whitepaper_pdf/RS_Making%20Mobile%20Seamless_whitepaper_web.pdf?cm_mmc=managed-_-cloud-_-contentnam-_-javascript-seamless) and learn how you can build your mobile app to create the effect that mobile devices are always connected. RackspaceSponsor [Papa Parse: A Powerful In-Browser JavaScript CSV Parser](http://papaparse.com/) Formerly known as the jQuery Parse Plugin. An excellent example of a well written project homepage that shows off what a library does. [Improve Your Tests by Breaking the Rules](http://bocoup.com/weblog/breaking-rules-in-tests/) How many JS ‘best practices’ can be irrelevant in test environments. Bocoup [It's Not Hard: Making Your Library Support AMD and CommonJS](http://ifandelse.com/its-not-hard-making-your-library-support-amd-and-commonjs/) Jim Cowart [The Introduction to Reactive Programming (in JavaScript) You've Been Missing](https://gist.github.com/staltz/868e7e9bc2a7b8c1f754) André Staltz Jobs - [Software Engineer (Frontend) at Uber](http://grnh.se/gfdoj6?utm_source=javascriptweekly&utm_medium=email)As a Frontend Software Engineer at Uber, you work well with designers, value a great user experience, and love all things HTML, CSS, and JavaScript. Uber - [Javascript Engineer at VerticalResponse](http://hire.jobvite.com/j/?cj=o719Zfw0=JavascriptWeekly)JavaScript engineer with a passion for developing advanced web applications using object oriented techniques? Eager to work with JavaScript/Rmber.js/Ember Data/HTML5/CSS3/Ruby on Rails/Redis/Postgres? If so, come join us. VerticalResponse - [Javascript Devs are in High Demand (SF, LA, NY)](http://ext.careercommits.com/javascriptwanted?utm_source=javascriptweekly&utm_medium=email)Apply once, get 5-15 job offers from the top tech companies. Explore your options - there are 997 companies bidding on talented Javascript devs just like you. Now hiring in San Francisco, Los Angeles, and New York. Apply for free today. CareerCommits In Brief [Object.observe() is now in Chrome Stable](https://twitter.com/addyosmani/status/489538862000394240) news Addy Osmani [React v0.11 Released](http://facebook.github.io/react/blog/2014/07/17/react-v0.11.html) news Paul O’Shannessy [Ember 1.6.1 Released (a small bug-fix release)](http://emberjs.com/blog/2014/07/15/ember-1-6-1-released.html) news Ember.js [An Approach to Developing and Testing Third Party JavaScript Widgets](https://www.youtube.com/watch?v=QmesIibMULY) video Nathan Artz [Hacking A HTML Renderer in Plain Browser-Side JS](https://www.youtube.com/watch?v=X4NP6DnVOsk) video Christoph Burgmer [Ensure You Are Not Adding To Global Scope in JavaScript](http://ardalis.com/ensure-you-are-not-adding-to-global-scope-in-javascript) tutorial By counting the number of objects in the global space or by using strict mode. Ardalis [How AngularJS Implements Dirty Checking and How to Replicate It Ourselves](http://ryanclark.me/how-angularjs-implements-dirty-checking/) tutorial Ryan Clark [Using an LED Matrix Display from Node.js with Johnny-Five](http://bocoup.com/weblog/javascript-led-matrix-display-with-johnny-five/) tutorial Bocoup [AngularJS for Absolute Beginners](http://medialoot.com/blog/angularjs-for-absolute-beginners/) tutorial Medialoot [11 JavaScript Interview Questions and Answers](http://www.toptal.com/javascript/interview-questions) Toptal [Optimizing Dynamic JavaScript with Inline Caches](https://github.com/sq/JSIL/wiki/Optimizing-dynamic-JavaScript-with-inline-caches) Katelyn Gadd [Deprecating the 'switch' Statement for Object Literals](http://toddmotto.com/deprecating-the-switch-statement-for-object-literals/) Todd Motto [Web Components Aren’t Ready for Production... Yet](http://developer.telerik.com/featured/web-components-arent-ready-production-yet/) TJ VanToll [Rome: A Dependency Free, Opt-in UI, Customizable Date (and Time) Picker](https://github.com/bevacqua/rome) code Nicolas Bevacqua [ConstraintJS: Define Automatically Maintained Relationships between Page Elements](http://cjs.from.so/) code CMU Natural Programming Group [Autopolyfiller: Precise Polyfills for the Targeted Environments](https://github.com/azproduction/autopolyfiller) code Autopolyfiller scans your code for polyfills then applies or removes only those relevant to the targeted environments. Mikhail Davydov [buddy.js: 'Magic Number' Detection for JavaScript](https://github.com/danielstjules/buddy.js) code In this context, ‘magic numbers’ means values littered through code that could more ideally be replaced with named constants. Daniel St. Jules [Trumbowyg: A Lightweight WYSIWYG Editor jQuery Plugin](http://alex-d.github.io/Trumbowyg/) code Alexandre Demode [_s: Pythonic Array Slicing in JavaScript](https://github.com/usablica/_s) code usabli.ca [Announcing JS Error Reporting + AJAX Timing in New Relic](http://blog.newrelic.com/2014/03/13/javascript-error-reporting-ajax-timing-new-relic/?utm_source=COOP=email=BlogNRBrowserAnnounce=PeterCooperNL=EM-COOP-generic-EN-100-HTML5Weekly-BlogNRBrowserAnnounce) Currently, 1.2m domains use the New Relic Browser monitoring tools to maintain a comprehensive overview of their browser page load times, throughput, browser transactions, JavaScript errors and Ajax timing. Find out how real-time insights help people build better performing software with New Relic. New RelicSponsor Curated by [Peter Cooper](http://twitter.com/peterc) and published by [Cooperpress](https://cooperpress.com/). Like this? You may also enjoy: [FrontEnd Focus](http://frontendfocus.co/) : [Node Weekly](http://nodeweekly.com/) : [React Status](http://react.statuscode.com/) [Stop getting JavaScript Weekly](*|UNSUB|*) : [Change email address](*|UPDATE_PROFILE|*) : [Read this issue on the Web](http://javascriptweekly.com/issues/190) © Cooperpress Ltd. Fairfield Enterprise Centre, Lincoln Way, Louth, LN11 0LS, UK