August 2015
Intermediate to advanced
168 pages
3h 44m
English
Content preview from Beautiful JavaScript
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
CHAPTER EIGHT
Evolution
In March 2009, Paul Irish published a blog post, “Markup-based Unobtrusive Comprehensive DOM-ready Execution,” describing a solution to a pesky problem familiar to every newcomer to the world of client-side JavaScript at the time: executing only the code that was required for a given page.
Back in 2009, it was common for client-side JavaScript developers to just put
all of their code—for all of their pages—inside one giant
$(document).ready() callback; some were a bit cleverer, and
tested for the presence of an element with a certain ID in order to
determine the page they were on. A newcomer to such code struggled
mightily to mentally parse hundreds of lines where function
declarations, anonymous functions, and long chains of jQuery methods
intermingled.
The method proposed in this blog post was simple: put a class on the
<body> element, and then use a simple helper function to look up a
corresponding initialization method in an application object:
UTIL={loadEvents:function(){varbodyId=document.body.id;$.each(document.body.className.split(/\s+/),function(i,className){UTIL.fire(className);UTIL.fire(className,bodyId);});},fire:function(func,funcname,args){varnamespace=APP;// indicate your obj literal namespace herefuncname=(funcname===undefined)?'init':funcname;if(func!==''&&namespace[func]&&typeofnamespace[func][funcname]=='function'){namespace[func][funcname](args);}}};$(document ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.