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Declarative Elements versus JavaScript and CSS

Over time as I looked at several of the new elements in HTML5, I saw a trend: many of the elements are single purpose derivations of popular, and commonly occurring, JavaScript and CSS applications. Consider the following list:

  • the progress element
  • the meter element
  • the hidden attribute
  • the details element
  • the telephone input type
  • the email input type
  • the search input type
  • the color picker
  • various date pickers

As I wrote in one of the change proposals, any one of these would have be welcome ten years ago, when HTML4 was released. But now, after we’ve come so far with using JavaScript and CSS, not to mention SVG and the Canvas element—what is the lesson we’re learning from these additions?

Ten years ago, support for CSS and JavaScript was poor enough that something like a color picker was almost impossible, unless you used Flash. Now, though, there are dozens of good libraries available that can implement a color picker. Drupal’s color picker is based on the jQuery UI, but it’s not the only option.

We’ve also had date pickers for years, too. Date pickers in all shapes and sizes, and most configurable by the user so they can get the absolute best date picking experience. The same can be said for progress bars, and if meter is supposed to represent a gauge, there are libraries that provide gauges, too.

As for the input types, such as telephone and email, most of the validation for these types of values can be handled with one line a code and a regular expression. The types also beg the question: where does it end? If we need single purpose data types such as telephone and email, why stop there? What about social security number for people in the states, or zip and/or postal codes?

One of the primary reasons for regular expressions in JavaScript is to ensure that a given string fits a given format. If we don’t know how to use regular expressions, that’s OK, because just like the iPhone, there’s a app for that. There are many libraries that automate the format validation for us. All we have to is assign a class to the relevant input fields.

The new elements, attribute, and input types aren’t just treading in JavaScript and CSS territory. Supposedly the reason for the hidden attribute is accessibility, as is a reason for several of the other elements. Yet the WAI-ARIA effort has provided the exact same functionality and semantics that can be used and reused with any number of elements.

ARIA is to accessibility, as JavaScript is to behavior, as CSS is to style, as RDFa/Microformats/Microdata are to semantics, and as HTML is to structure. Except, suddenly, HTML is no longer about structure. The clean separation between the various domains that has worked so well in the past is seemingly no longer of interest to the HTML WG. Consider the following statement in the HTML5 specification:

Authors are encouraged to use declarative alternatives to scripting where possible, as declarative mechanisms are often more maintainable, and many users disable scripting.

For example, instead of using script to show or hide a section to show more details, the details element could be used.

Why?

The arguments I’ve read are that declarative alternatives can be used by non-developers, but they’re no easier for non-developers to use than most of the JavaScript libraries I know, which usually only require adding a class to an element.

I’ve also read that declarative alternatives aren’t impacted when JavaScript is turned off, but in my opinion, that’s not a good thing. People have become used to JavaScript-based functionality on the web. They know if a section is exposed via JavaScript that turning off the JavaScript should display the section by default. People can control JavaScript and Flash in their browsers, which means they can control the behavior of the web page. They can also turn off CSS, if they wish. But they have no control over declarative elements and animations.

Consider, too, the costs involved with all these new elements and other objects. Rather than browser developers focused on making the most efficient JavaScript engine, the most secure browser, adding support for SVG and Canvas, Video, WebGL, and any of the other new technologies, the developers now have to focus on what is nothing more than a duplication of functionality already available via libraries, apps, and widgets. Which they also have to support through the core technologies of CSS and JavaScript.

Then consider all of the HTML editors and WYSIWYG tools that now have to add several new input types and elements, including having to provide a live preview of the functionality. Implementing all these new elements, attributes, and input types must seem a daunting task.

How about the web authors and designers? New toys, eh?

New toys that lack both the sophistication and customization capability that we’ve had with our existing libraries. New toys that aren’t accessible until we can convince the screen readers that no, seriously, not only do they have to support ARIA, they have to support all these other new things, too.

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