Tags: extensible

Eigensolutions: composability as the antidote to overfit • Lea Verou

I love, love, love the deep thinking that Lea has put into this, really digging into the guts of what design does.

Overfitting happens when solutions don’t generalize sufficiently and is a hallmark of poor design. Eigensolutions are the opposite: solutions that generalize so much they expose links between seemingly unrelated use cases. Designing eigensolutions takes a mindset shift from linear design to composability.

Lea ties this into web standards too. It’s really helped clarify for me why I want more declarative options for common use cases (like a share button)—it’s about raising the ceiling without raising the floor.

Open UI and implicit parent/child relationships in HTML – Eric Bailey

I remember discussing this with Tantek years ago:

There are a few elements who need to be placed inside of another specific element in order to function properly.

If I recall, he was considering writing “HTML: The Good Parts”.

Anyway, I can relate to what Eric is saying here about web components. My take is that web components give developers a power that previous only browser makers had. That’s very liberating, but it should come with a commensurate weight of responsibility. I fear that we will see this power wielded without sufficient responsibility.

Building an extensible app or library with vanilla JS | Go Make Things

This looks like a sensible approach to creating a modular architecture for a complex client-side JavaScript codebase.

I know a lot of people swear by ES6 imports, but this systems worked really well for us. It gave us a simple, modular, extensible framework we can easily build on in the future.

Toast

Chris describes exactly why I wrote about toast:

But we should be extra watchful about stuff like this. If any browser goes rogue and just starts shipping stuff, web standards is over. Life for devs gets a lot harder and the web gets a lot worse. The stakes are high. And it’s not going to happen overnight, it’s going to happen with little tiny things like this. Keep that blue beanie on.

Shockwaves rippled across the web standards community recently when it appeared that Google Chrome was unilaterally implementing a new element called toast. It turns out that’s not the case, but the confusion is understandable.

First off, this all kicked off with the announcement of “intent to implement”. That makes it sounds like Google are intending to, well, …implement this. In fact “intent to implement” really means “intend to mess around with this behind a flag”. The language is definitely confusing and this is something that will hopefully be addressed.

Secondly, Chrome isn’t going to ship a toast element. Instead, this is a proposal for a custom element currently called std-toast. I’m assuming that should the experiment prove successful, it’s not a foregone conclusion that the final element name will be called toast (minus the sexually-transmitted-disease prefix). If this turns out to be a useful feature, there will surely be a discussion between implementators about the naming of the finished element.

This is the ideal candidate for a web component. It makes total sense to create a custom element along the lines of std-toast. At first I was confused about why this was happening inside of a browser instead of first being created as a standalone web component, but it turns out that there’s been a fair bit of research looking at existing implementations in libraries and web components. So this actually looks like a good example of paving an existing cowpath.

But it didn’t come across that way. The timing of announcements felt like this was something that was happening without prior discussion. Terence Eden writes:

It feels like a Google-designed, Google-approved, Google-benefiting idea which has been dumped onto the Web without any consideration for others.

I know that isn’t the case. And I know how many dedicated people have worked hard on this proposal.

Adrian Roselli also remarks on the optics of this situation:

To be clear, while I think there is value in minting a native HTML element to fill a defined gap, I am wary of the approach Google has taken. A repo from a new-to-the-industry Googler getting a lot of promotion from Googlers, with Googlers on social media doing damage control for the blowback, WHATWG Googlers handling questions on the repo, and Google AMP strongly supporting it (to reduce its own footprint), all add up to raise alarm bells with those who advocated for a community-driven, needs-based, accessible web.

Dave Cramer made a similar point:

But my concern wasn’t so much about the nature of the new elements, but of how we learned about them and what that says about how web standardization works.

So there’s a general feeling (outside of Google) that there’s something screwy here about the order of events. A lot discussion and research seems to have happened in isolation before announcing the intent to implement:

It does not appear that any discussions happened with other browser vendors or standards bodies before the intent to implement.

Why is this a problem? Google is seeking feedback on a solution, not on how to solve the problem.

Going back to my early confusion about putting a web component directly into a browser, this question on Discourse echoes my initial reaction:

Why not release std-toast (and other elements in development) as libraries first?

It turns out that std-toast and other in-browser web components are part of an idea called layered APIs. In theory this is an initiative in the spirit of the extensible web manifesto.

The extensible web movement focused on exposing low-level APIs to developers: the fetch API, the cache API, custom elements, Houdini, and all of those other building blocks. Layered APIs, on the other hand, focuses on high-level features …like, say, an HTML element for displaying “toast” notifications.

Layered APIs is an interesting idea, but I’m worried that it could be used to circumvent discussion between implementers. It’s a route to unilaterally creating new browser features first and standardising after the fact. I know that’s how many features already end up in browsers, but I think that the sooner that authors, implementers, and standards bodies get a say, the better.

I certainly don’t think this is a good look for Google given the debacle of AMP’s “my way or the highway” rollout. I know that’s a completely different team, but the external perception of Google amongst developers has been damaged by the AMP project’s anti-competitive abuse of Google’s power in search.

Right now, a lot of people are jumpy about Microsoft’s move to Chromium for Edge. My friends at Microsoft have been reassuring me that while it’s always a shame to reduce browser engine diversity, this could actually be a good thing for the standards process: Microsoft could theoretically keep Google in check when it comes to what features are introduced to the Chromium engine.

But that only works if there is some kind of standards process. Layered APIs in general—and std-toast in particular—hint at a future where a single browser vendor can plough ahead on their own. I sincerely hope that’s a misreading of the situation and that this has all been an exercise in miscommunication and misunderstanding.

Like Dave Cramer says:

I hear a lot about how anyone can contribute to the web platform. We’ve all heard the preaching about incubation, the Extensible Web, working in public, paving the cowpaths, and so on. But to an outside observer this feels like Google making all the decisions, in private, and then asking for public comment after the feature has been designed.

Create a MarkDown tag - JSFiddle

This is nice example of a web component that degrades gracefully—if custom elements aren’t supported, you still get the markdown content, just not converted to HTML.

<ah-markdown>
## Render some markdown!
</ah-markdown>

Shadow DOM v1: self-contained web components | Web Fundamentals - Google Developers

An in-depth look at the current Shadow DOM spec. It’s well-written but I don’t think this will really click with me until I start playing around with it for myself.

It’s good to see that the examples have some thought given to fallback content.

There’s also a corresponding tutorial on custom elements

Adam Onishi has written up his thoughts on web components and progressive enhancements, following on from a discussion we were having on Slack. He shares a lot of the same frustrations as I do.

Two years ago, I said:

I have conflicting feelings about Web Components. I am simultaneously very excited and very nervous.

I still feel that way. In theory, web components are very exciting. In practice, web components are very worrying. The worrying aspect comes from the treatment of backwards compatibility.

It all comes down to the way custom elements work. When you make up a custom element, it’s basically a span.

<fancy-select></fancy-select>

Then, using JavaScript with ShadowDOM, templates, and the other specs that together make up the web components ecosystem, you turn that inert span-like element into something all-singing and dancing. That’s great if the browser supports those technologies, and the JavaScript executes successfully. But if either of those conditions aren’t met, what you’re left with is basically a span.

One of the proposed ways around this was to allow custom elements to extend existing elements (not just spans). The proposed syntax for this was an is attribute.

<select is="fancy-select">...</select>

Browser makers responded to this by saying “Nah, that’s too hard.”

To be honest, I had pretty much given up on the is functionality ever seeing the light of day, but Monica has rekindled my hope:

@adactio I will go to every standards meeting until I get it done, because otherwise we are hosed for <form> and web components.

— Monica Dinosaurescu (@notwaldorf) June 16, 2016

Still, I’m not holding my breath for this kind of declarative extensibility landing in browsers any time soon. Instead, a JavaScript-based way of extending existing existing elements is currently the only way of piggybacking on all the accessible behavioural goodies you get with native elements.

class FancySelect extends HTMLSelectElement

But this imperative approach fails completely if custom elements aren’t supported, or if the JavaScript fails to execute. Now you’re back to having spans.

The presentation on web components at the Progressive Web Apps Dev Summit referred to this JavaScript-based extensibility as “progressively enhancing what’s already available”, which is a bit of a stretch, given how completely it falls apart in older browsers. It was kind of a weird talk, to be honest. After fifteen minutes of talking about creating elements entirely from scratch, there was a minute or two devoted to the is attribute and extending existing elements …before carrying as though those two minutes never happened.

But even without any means of extending existing elements, it should still be possible to define custom elements that have some kind of fallback in non-supporting browsers:

<fancy-select>
 <select>...</select>
</fancy-select>

In that situation, you at least get a regular ol’ select element in older browsers (or in modern browsers before the JavaScript kicks in and uplifts the custom element).

Adam has a great example of this in his post:

I’ve been thinking of a gallery component lately, where you’d have a custom element, say <o-gallery> for want of a better example, and simply populate it with images you want to display, with custom elements and shadow DOM you can add all the rest, controls/layout etc. Markup would be something like:

<o-gallery>
 <img src="">
 <img src="">
 <img src="">
</o-gallery>

If none of the extra stuff loads, what do we get? Well you get 3 images on the page. You still get the content, but just none of the fancy interactivity.

Yes! This, in my opinion, is how we should be approaching the design of web components. This is what gets me excited about web components.

Then I look at pretty much all the examples of web components out there and my nervousness kicks in. Hardly any of them spare a thought for backwards-compatibility. Take a look, for example, at the entire contents of the body element for the Polymer Shop demo site:

<shop-app unresolved="">SHOP</shop-app>

This seems really odd to me, because I don’t think it’s a good way to “sell” a technology.

Compare service workers to web components.

First of all, ask the question “who benefits from this technology?” In the case of service workers, it’s the end users. They get faster websites that handle network failure better. In the case of web components, there are no direct end-user benefits. Web components exist to make developers lives easier. That’s absolutely fine, but any developer convenience gained by the use of web components can’t come at the expense of the user—that price is too high.

The next question we usually ask when we’re evaluating a technology is “how well does it work?” Personally, I think it’s just as important to ask “how well does it fail?”

Service workers work well and fail well. If a browser supports service workers, the user gets all the benefits. If a browser doesn’t support service workers, the user get the same experience they would have always had.

Web components (will) work well, but fail badly. If a browser supports web components, the user gets the experience that the developer has crafted using these new technologies. If a browser doesn’t support web components, the user gets …probably nothing. It depends on how the web components have been designed.

It’s so much easier to get excited about implementing service workers. You’ve literally got nothing to lose and everything to gain. That’s not the case with web components. Or at least not with the way they are currently being sold.

See, this is why I think it’s so important to put some effort into designing web components that have some kind of fallback. Those web components will work well and fail well.

Look at the way new elements are designed for HTML. Think of complex additions like canvas, audio, video, and picture. Each one has been designed with backwards-compatibility in mind—there’s always a way to provide fallback content.

Web components give us developers the same power that, up until now, only belonged to browser makers. Web components also give us developers the same responsibilities as browser makers. We should take that responsibility seriously.

Web components are supposed to be the poster child for The Extensible Web Manifesto. I’m all for an extensible web. But the way that web components are currently being built looks more like an endorsement of The Replaceable Web Manifesto. I’m not okay with a replaceable web.

Here’s hoping that my concerns won’t be dismissed as “piffle and tosh” again by the very people who should be thinking about these issues.

Web Components and progressive enhancement - Adam Onishi

Adam and I share the same hopes and frustrations with web components. They can be written in a resilient, layered way that allows for progressive enhancement, but just about every example out there demonstrates a “my way or the highway” approach to using them.

We were chatting about this in the Design Systems slack channel, and it helped clarify some of my thoughts. I’ll try to poop out a blog post about this soon.

shawnbot/custom-elements: All about HTML Custom Elements

A good introduction to custom elements, one piece of the web components stack.

That said, when using custom elements—or anything involving JavaScript, for that matter—you should always design experiences for progressive enhancement, and plan for the possibility that JavaScript isn’t enabled or available.

Hmmm …that’s kind of hard when JavaScript is required to make custom elements work at all.

I highly recommend Remy’s State Of The Gap post—it’s ace. He summarises it like this:

I strongly believe in the concepts behind progressive web apps and even though native hacks (Flash, PhoneGap, etc) will always be ahead, the web, always gets there. Now, today, is an incredibly exciting time to be build on the web.

I agree completely. That might sound odd after I wrote about Regressive Web Apps, but it’s precisely because I’m so excited by the technologies behind progressive web apps that I think it’s vital that we do them justice. As Remy says:

Without HTTPS and without service workers, you can’t add to homescreen. This is an intentionally high bar of entry with damn good reasons.

When the user installs a PWA, it has to work. It’s our job as web developers to provide the most excellent experience for our users.

It has to work.

That’s why I don’t agree with Dion’s metrics for what makes a progressive web app:

If you deliver an experience that only works on mobile is that a PWA? Yes.

I think it’s important to keep quality control high. Being responsive is literally the first item in the list of qualities that help define what a progressive web app is. That’s why I wrote about “regressive” web apps: sites that are supposed to showcase what we can do but instead take a step backwards into the bad old days of separate sites for separate device classes: washingtonpost.com/pwa, m.flipkart.com, lite.5milesapp.com, app.babe.co.id, m.aliexpress.com.

A lot of people on Twitter misinterpreted my post as saying “the current crop of progressive web apps are missing the mark, therefore progressive web apps suck”. What I was hoping to get across was “the current crop of progressive web apps are missing the mark, so let’s make better ones!”

Now, I totally understand that many of these examples are a first stab, a way of testing the waters. I absolutely want to encourage these first attempts and push them further. But I don’t think that waiving the qualifications for progressive web apps helps achieves that. As much as I want to acknowledge the hard work that people have done to create those device-specific examples, I don’t think we should settle for anything less than high-quality progressive web apps that are as much about the web as they are about apps.

Simply put, in this instance, I don’t think good intentions are enough.

Which brings me to the second part of Regressive Web Apps, the bit about Chrome refusing to show the “add to home screen” prompt for sites that want to have their URL still visible when launched from the home screen.

Alex was upset by what I wrote:

if you think the URL is going to get killed on my watch then you aren’t paying any attention whatsoever.

so, your choices are to think that I have a secret plan to kill URLs, or conclude I’m still Team Web.

I’m galled that anyone, particularly you @adactio, would think the former…but contrarianism uber alles?

I am very, very sorry that I upset Alex like this.

But I stand by my criticism of the actions of the Chrome team. Because good intentions are not enough.

I know that Alex is huge fan of URLs, and of the web. Heck, just about everybody I know that works on Chrome in some capacity are working for the web first and foremost: Alex, Jake, various and sundry Pauls. But that doesn’t mean I’m going to stay quiet when I see the Chrome team do something I think is bad for the web. If anything, it’s precisely because I hold them to a high standard that I’m going to sound the alarm when I see what I consider to be missteps.

I think that good people can make bad decisions with the best of intentions. Usually it involves long-term thinking—something I think is very important. “The ends justify the means” is a way of thinking that can create a lot of immediate pain, even if it means a better future overall. Balancing those concerns is front and centre of the Chromium project:

As browser implementers, we find that there’s often tension between (a) moving the web forward and (b) preserving compatibility. On one hand, the web platform API surface must evolve to stay relevant. On the other hand, the web’s primary strength is its reach, which is largely a function of interoperability.

For example, when Alex talks of the Web Component era as though it were an inevitability, I get nervous. Not for myself, but for the millions of Opera Mini users out there. How do we get to a better future without leaving anyone behind? Or do we sacrifice those people for the greater good? Do the needs of the many outweigh the needs of the few? Do the ends justify the means?

Now, I know for a fact that the end-game that Alex is pursuing with web components—and the extensible web manifesto in general—is a more declarative web: solutions that first get tackled as web components end up landing in browsers. But to get there, the solutions are first created using modern JavaScript that simply doesn’t work everywhere. Is that the price we’re going to have to pay for a better web?

I hope not. I hope we can find ways to have our accessible cake and eat it too. But it will be really, really hard.

Returning to progressive web apps, I was genuinely shocked and appalled at the way that the Chrome team altered the criteria for the “add to home screen” prompt to discourage exposing URLs. I was also surprised at how badly the change was communicated—it was buried in a bug report that five people contributed to before pushing the change. I only found out about it through a conversation with Paul Kinlan. Paul encouraged me to give feedback, and that’s what I did on my website, just like Stuart did on his.

Of course the Chrome team are working on ways of exposing URLs within progressive web apps that are launched in from the home screen. Opera are working on it too. But it’s a really tricky problem to solve. It’s not enough to say “we’ll figure it out”. It’s not enough to say “trust us.”

I do trust the people I know working on Chrome. I also trust the people I know at Mozilla, Opera and Microsoft. That doesn’t mean I’m going to let their actions go unquestioned. Good intentions are not enough.

As Alex readily acknowledges, the harder problem (figuring out how to expose URLs) should have been solved first—then the change to the “add to home screen” metrics would be uncontentious. Putting the cart before the horse, discouraging display:browser now, while saying “trust us, we’ll figure it out”, is another example of saying the ends justify the means.

But the stakes are too high here to let this pass. Good intentions are not enough. Knowing that the people working on Chrome (or Firefox, or Opera, or Edge) are good people is not reason enough to passively accept every decision they make.

Alex called me out for not getting in touch with him directly about the Chrome team’s future plans with URLs, but again, that kind of rough consensus to do something is trumped by running code. Also, I did talk to Chrome people—this all came out of a discussion with Paul Kinlan. I don’t know who’s who in the company’s political hierarchy and I don’t think I should need an org chart to give feedback to Google (or Mozilla, or Opera, or Microsoft).

You’ll notice that I didn’t include Apple there. I don’t hold them to the same high standard. As it turns out, I know some very good people at Apple working on WebKit and Safari. As individuals, they care about the web. But as a company, Apple has shown indifference towards web developers. As Remy put it:

Even getting the hint of interest from Apple is a process of dumpster-diving the mailing lists scanning for the smallest hint of interest.

With that in mind, I completely understand Alex’s frustration with my post on “regressive” web apps. Although I intended it as a push towards making better progressive web apps, I can see how it could be taken as confirmation by those who think that progressive web apps aren’t worth investing in. Apple, for example. As it is, they’ll have to be carried kicking and screaming into adding support for Service Workers, manifest files, and other building blocks. From the reaction to my post from at least one WebKit developer on Twitter, not only did I fail to get across just how important the technologies behind progressive web apps are, I may have done more harm than good, giving ammunition to sceptics.

Still, I hope that most people took my words in the right spirit, like Addy:

We should push them to do much better. I’ll file bugs. Per @adactio post, can’t forget the ‘Progressive’ part of PWAs

Seeing that reaction makes me feel good …but seeing Alex’s reaction makes me feel bad. Very bad. I’m genuinely sorry that I made Alex feel that way. It wasn’t my intention but, well …good intentions are not enough.

I’ve been looking back at what I wrote, trying to see it through Alex’s eyes, looking for the parts that could be taken as a personal attack:

Chrome developers have decided that displaying URLs is not “best practice” … To declare that all users of all websites will be confused by seeing a URL is so presumptuous and arrogant that it beggars belief. … Withholding the “add to home screen” prompt like that has a whiff of blackmail about it. … This isn’t the first time that Chrome developers have made a move against the address bar. It’s starting to grind me down.

Some pretty strong words there. I stand by them, but the tone is definitely strident.

When we criticise something—a piece of software, a book, a website, a film, a piece of music—it’s all too easy to forget that there are real people behind it. But that isn’t the case here. I know that there are real people working on Chrome, because I know quite a few of those people. I also know that their intentions are good. That’s not a reason for me to remain silent—that’s a reason for me to speak up.

If I had known that my post was going to upset Alex, would I have still written it? That’s a tough one. On the one hand, this is a topic I care passionately about. I think it’s vital that we don’t compromise on the very things that make the web great. On the other hand, who knows if what I wrote will make the slightest bit of difference? In which case, I got the catharsis of getting it off my chest but at the price of upsetting somebody I respect. That price feels too high.

I love the fact that I can publish whatever I want on my own website. It can be a place for me to be enthusiastic about things that excite me, and a place for me to rant about things that upset me. I estimate that the enthusiastic stuff outnumbers the ranty stuff by about ten to one, but negativity casts a disproportionately large shadow.

I need to get better at tempering my words. Not that I’m going to stop criticising bad decisions when I see them, but I need to make my intentions clearer …because just having good intentions is not enough. Throughout this post, I’ve mentioned repeatedly how much I respect the people I know working on the Chrome team. I should have said that in my original post.

Surma.link – New ways to make your web app jank with Houdini – An introduction

This is a really good primer on all the pieces that make up the Houdini approach to CSS—giving authors access to low-level APIs for rendering.

As is often repeated here, it’s still early days and caution is advised, but it’s still a good idea to wrap your head around what’s coming down the standards pipe.

There’s even more specs in Houdini’s list of drafts, but the future of those is rather uncertain and they are not much more than a placeholder for an idea at this point. Examples include custom overflow behaviors, CSS syntax extension API, extension of native scroll behavior and similar ambitious things that allow you to screw up your web app even worse than ever before. Rejoice!

Practical Questions around Web Components - Ian Feather

An in-depth look at where web components stand today, together with some very good questions about where they might be heading tomorrow.

Contrary to popular belief, web standards aren’t created by a shadowy cabal and then handed down to browser makers to implement. Quite the opposite. Browser makers come together in standards bodies and try to come to an agreement about how to collectively create and implement standards. That keeps them very busy. They don’t tend to get out very often, but when they do, the browser/standards makers have one message for developers: “We want to make your life better, so tell us what you want and that’s what we’ll work on!”

In practice, this turns out not to be the case.

Case in point: responsive images. For years, this was the number one feature that developers were crying out for. And yet, the standards bodies—and, therefore, browser makers—dragged their heels. First they denied that it was even a problem worth solving. Then they said it was simply too hard. Eventually, thanks to the herculean efforts of the Responsive Images Community Group, the browser makers finally began to work on what developers had been begging for.

Now that same community group is representing the majority of developers once again. Element queries—or container queries—have been top of the wish list of working devs for quite a while now. The response from browser makers is the same as it was for responsive images. They say it’s simply too hard.

Here’s a third example: web components. There are many moving parts to web components, but one of the most exciting to developers who care about accessibility and backwards-compatibility is the idea of extending existing elements:

It’s my opinion that, for as long as there is a dependence on JS for custom elements, we should extend existing elements when writing custom elements. It makes sense for developers, because new elements have access to properties and methods that have been defined and tested for many years; and it makes sense for users, as they have fallback in case of JS failure, and baked-in accessibility fundamentals.

So instead of having to create a whole new element from scratch like this:

<taco-button>Click me!</taco-button>

…you could piggy-back on an existing element like this:

<button is="taco-button">Click me!</button>

That way, you get the best of both worlds: the native semantics of button topped with all the enhancements you want to add with your taco-button custom element. Brilliant! Github is using this to extend the time element, for example.

I’m not wedded to the is syntax, but I do think it’s vital that there is some declarative mechanism to extend existing elements instead of creating every custom element from scratch each time.

Now it looks like that’s the bit of web components that isn’t going to make the cut. Why? Because browser makers say it’s simply too hard.

As Bruce points out, this is in direct conflict with the design principles that are supposed to be driving the creation and implementation of web standards.

It probably wouldn’t bother me so much except that browser makers still trot out the party line, “We want to hear what developers want!” Their actions demonstrate that this claim is somewhat hollow.

I don’t hold out much hope that we’ll get the ability to extend existing elements for web components. I think we can still find ways to piggy-back on existing semantics, but it’s going to take more work:

<taco-button><button>Click me!</button></taco-button>

That isn’t very elegant and I can foresee a lot of trickiness trying to sift the fallback content (the button tags) from the actual content (the “Click me!” text).

But I guess that’s what we’ll be stuck with. The alternative is simply too hard.

How GitHub is using Web Components in production — WebComponents.org

With all my talk about extending existing elements instead of making new ones, I was reminded of one of my favourite examples of custom elements in action: Github’s extensions of the time element.

Bruce has written a great article called On the accessibility of web components. Again. In it, he takes issue with the tone of a recent presentation on web components, wherein Dimitri Glazkov declares:

Custom elements is really neat. It basically says, “HTML it’s been a pleasure”.

Bruce paraphrases this as:

Bye-bye HTML; you weren’t useful enough. Hello, brave new world of custom elements.

Like Bruce, I’m worried about this year-zero thinking. First of all, I think it’s self-defeating. In my experience, the web technologies that succeed are the ones that build upon what already exists, rather than sweeping everything aside. Evolution, not revolution.

Secondly, web components—or more specifically, custom elements—already allow us to extend existing HTML elements. That means we can use web components as a form of progressive enhancement, turbo-charging pre-existing elements instead of creating brand new elements from scratch. That way, we can easily provide fallback content for non-supporting browsers.

But, as Bruce asks:

Snarking aside, why do so few people talk about extending existing HTML elements with web components? Why’s all the talk about brand new custom elements? I don’t know.

Patrick leaves a comment with his answer:

The issue of not extending existing HTML elements is exactly the same that we’ve seen all this time, even before web components: developers who are tip-top JavaScripters, who already plan on doing all the visual feedback/interactions (for mouse users like themselves) in script anyway themselves, so they just opt for the most neutral starting point…a div or a span. Web components now simply gives the option of then sweeping all that non-semantic junk under a nice, self-contained rug.

That’s a depressing thought. But it might very well be true.

Stuart also comments:

Why aren’t web components required to be created with is=“some-component” on an existing HTML element? This seems like an obvious approach; sure, someone who wants to make something meaningless will just do <div is=my-thing> or (worse) <body is=my-thing> but it would provide a pretty heavy hint that you’re supposed to be doing things The Right Way, and you’d get basic accessibility stuff thrown in for free.

That’s a good question. After all, writing <new-shiny></new-shiny> is basically the same as <span is=“new-shiny”></span>. It might not make much of a difference in the case of a span or div, but it could make an enormous difference in the case of, say, form elements.

Take a look at IBM’s library of web components. They’re well-written and they look good, but time and time again, they create new custom elements instead of extending existing HTML.

• <d-checkbox> and <d-switch> instead of <input type=“checkbox” is=“d-checkbox”> and <input type=“checkbox” is=“d-switch”>
• <d-progress-bar> instead of <progress is=“d-progress-bar”>
• <d-combobox><d-list> instead of <input is=“d-combo-box”><datalist is=“d-list”>

Although, as Bruce points out:

Of course, not every new element you’ll want to make can extend an existing HTML element.

But I still think that the majority of web components could, and should, extend existing elements. Addy Osmani has put together some design principles for web components and Steve Faulkner has created a handy punch-list for web components, but I’d like to propose that a fundamental principle of good web component design should be: “Where possible, extend an existing HTML element instead of creating a new element from scratch.”

Rather than just complain about this kind of thing, I figured I’d try my hand at putting it into practice…

Dave recently made a really nice web component for playing back podcast audio files. I could imagine using something like this on Huffduffer. It’s called podcast-player and you use it thusly:

<podcast-player src="my.mp3"></podcast-player>

One option for providing fallback content would be to include it within the custom element tags:

<podcast-player src="my.mp3">
    <a href="my.mp3">Listen</a>
</podcast-player>

That would require minimum change to Dave’s code. I’d just need to make sure that the fallback content within podcast-player elements is removed in supporting browsers.

I forked Dave’s code to try out another idea. I figured that if the starting point was a regular link to the audio file, that would also be a way of providing fallback for browsers that don’t cut the web component mustard:

<a href="my.mp3" is="podcast-player">Listen</a>

It required surprisingly few changes to the code. I needed to remove the fallback content (that “Listen” text), and I needed to prevent the default behaviour (following the href), but it was fairly straightforward.

However, I’m sure it could be improved in one of two ways:

1. I should probably supply an ARIA role to the extended link. I’m not sure what would be the right one, though …menu or menubar perhaps?
2. Perhaps a link isn’t the right element to extend. Really I should be extending an audio element (which itself allows for fallback content). When I tried that, I found it too hard to overcome the default browser rules for hiding anything between the opening and closing tags. But you’re smarter than me, so I bet you could create <audio is=“podcast-player”>.

Fork the code and have at it.

Extensible Web Summit Berlin 2014: my lightning talk on Web Components | soledad penadés

Soledad Penadés also went to the Extensible Web Summit in Berlin, where she gave a lightning talk. Sounds like it was really good.

This also includes some good advice that, again, Alex might want to consider before denouncing any disagreement on Web Components as “piffle and tosh”:

If the W3C, or any other standardisation organisation wants to attract “normal” developers to get more diverse inputs, they/we should start by being respectful to everyone. Don’t try to show everyone how superclever you are. Don’t be a jerk. Don’t scare people away, because then only the loud ones stay, and the quieter shy people, or people who have more urgent matters to attend (such as, you know, having a working business website even if it’s not using the latest and greatest API) will just leave.

Bruce Lawson’s personal site  : Reflections on Extensible Web Summit, Berlin

Bruce went to the Extensible Web Summit in Berlin and wrote up his notes.

Sounds like he shares my excitement, but also my nervousness.

I’m not yet entirely convinced that we’re not heralding a new era of JavaScript-only web development. I don’t want to see the fossilisation of the declarative web and a new Programmer Priesthood (re-)emerge.

There’s also this important point, that Alex would do well to remember before crying “Piffle and tosh!”:

We need to ensure that all devs who want to can participate by allowing ease of collaboration, courteous discourse.

Notes on notes (of smart people) about web components

Steve Faulkner responds to Alex’s response to my post about Web Components.

Steve shares my concerns …but he still refers to my post as “piffle”.

I can’t win.

Uncomfortably Excited – Infrequently Noted

Alex’s response to my post about Web Components, in which he ignores my excitement and dismisses my concerns as “piffle and tosh.”

I gotta say: I think cautious optimism and nervous excitement are healthy attitudes to have about any technology. For Alex to dismiss them so summarily makes me even more worried. Apparently you’re either with Web Components or you’re against them. Heaven forbid that you might voice any doubts or suggest any grey areas.

The beatings will continue until morale improves.