[general_failure]

I am mostly a systems dev but I have written my share of websites. They are all built with just jQuery. Can someone englighten me the need for data bindings and all these frameworks?

For example, say, github.com. Where in that website would I use data bindings? Or say gmail for that matter. The idea of bindings is not alien to me but I just fail to appreciate why bindings are useful for most websites.

(I do understand backbone.js but I just feel I can write what I want in a observer/listener pattern in 20 mins instead of bothering to learn all intricacies of a framework)

[nolok]

* not useful in github (simple page with some js extras on top, it's a prime job for jquery)

* for gmail you would use it to handle emails for example. Your view in gmail never changes, if you're looking at tags, or archive, or sent mails, or inbox, ... It's always the same thing, but the dataset changes; it comes from different sources, it is sorted and filtered different, ...

For a Gmail clone with angular, you do you app/html/css one time, and then you only ever manipulate your model, everything else is done for you. Want to filter email to only get those tagged "hacker news" ? Map reduce your email set then assign it to your model, that's it - no dom no event assign no view logic no nothing, only data.

Now, I'm pretty sure you read this and you think "but I could do the same with what I'm used to, just create a setEmailList(emails) function and use it", that is entirely true. Angular does not provide new functionnalities that you couldn't get otherwise. What angular provide is that

1 - it will be way faster to code than your "traditionnal" method once you're used to it, because angular does most of it for you, and

2 - large changes, special cases and thus evolution of the app are much easier to handle and code.

It provide those two things by being made explicitely for them. Angular is so tailored for that use case that it sucks and should never be used for anything else. Don't be fooled by all the hype into thinking every website should now use angular/ember/whatever, they shouldn't. It does only one kind of job, but it does it very, very well.

[Volpe]

While this isn't really the place to explain it. What takes you 20 minutes with observer listener pattern takes less than 1 in angular (can't speak for ember). It is life changing if you've always hand rolled your own JS.

There is not too much to either of these frameworks. A solid day and you'll be productive. There are many layers to becoming an expert, but (at least with angular) you can just use the bits you know, and refactor as you learn more.

i.e. You don't have to know anything about what "directives" are to build an app

[perlgeek]

jQuery is great for progressive enhancement. Github serves mostly static pages, and then some javascript that adds a bit of functionality on top.

But consider writing a spreadsheet application instead, where changing one cell can influence a lot of others. That seems like a good use case for data binding (though I admit I haven't used it so far).

[EugeneOZ]

Each time I'm looking at the code of my previous web apps which are built with jQuery, I think how many boilerplate code here, could be replaced by Angular-code in 3-4 times less amount of lines and without many bugs (copy-paste is their reason and it's my sin, but because of often repeated boilerplate code). But it's not enough reason to rewrite them :)

[hackula1]

Along with maintainability, which others have mentioned, I would throw out there that Angular is generally easier to test than your average jQuery scramble.