Posted by zigzag312 5 hours ago
The word "component" has to mean something ultimately, and to me the defining feature of a web component is that it's self-contained: it brings along its own dependencies, whether that's JavaScript, templates, CSS, etc. Web components shouldn't require an external framework or external CSS (except for customization by the user) - those things should be implementation details depended on directly by the component.
This here is just CSS using tag names for selectors. The element is doing nothing on its own.
Which is fine! It's just not web components.
edit: Also, don't do this:
<link-button>
<a href="">Learn more</a>
</link-button>
Use classes:
<a class="button" href="">Learn more</a>
You can read the entirety of War and Peace in a single HTML file: https://standardebooks.org/ebooks/leo-tolstoy/war-and-peace/...
A marketing page, SaaS app landing, etc., will not even begin to approach that size, whether or not you add an extra wrapper around your <a>s.
Marketing is in the end a way of trying to get people to listen, even if you have nothing substantial to say (or if you have something to say, potentially multiply the effect of that message). That means you have to invent a lot of packaging and fluff surrounding the thing you want to sell to change peoples impression independent of the actual substance they will encounter.
This to me is entirely backwards. If you want people to listen focus on your content, then make sure it is presented in a way that serves that content. And if we are talking about text, that is really, really small in terms of data and people will be happy if they can access it quickly and without 10 popups in their face.
Not that I accuse any person in this thread of towing that line, but the web as of today seems to be 99% of unneeded crap, with a tiny sprinkle of irrelevant content.
<swim-lane>
<style>
@scope {
background: pink;
b {
background: lightblue
}
@media (max-width: 650px) {
/* Mobile responsive styles */
}
}
</style>
something <b>cool</b>
</swim-lane>
@scope (swim-lane) { /* ... */ }
Shadow DOM is awful. Nobody should be using it for anything, ever. (It's required for putting child-element "slots" in custom elements, and so nobody should use those, either.) Shadow DOM is like an iframe in your page; styles can't escape the shadow root and they can't get into the shadow root, either. IDs are scoped in shadow roots, too, so the aria-labelledby attribute can't get in or out, either.
@scope is the right abstraction: parent styles can cascade in, but the component's styles won't escape the element, giving you all of the (limited) performance advantages of Shadow DOM with none of the drawbacks.
Counterpoint: Shadow DOM is great. People should be using it more. It's the only DOM primitive that allows for interoperable composition. Without it you're at the mercy of frameworks for being able to compose container components out of internal structure and external children.
Sort by negative sentiment; Shadow DOM is at the top of the list, the most hated feature in Web Components. You can read the comments, too, and they're almost all negative, and 100% correct.
"Accessibility nightmare"
"always hard to comprehend, and it doesn't get easier with time"
"most components don't need it"
"The big issue is you need some better way to some better way to incorporate styling from outside the shadow dom"
> It's the only DOM primitive that allows for interoperable composition.
There is no DOM primitive that allows for interoperable composition with fine-grained reactivity. Your framework offers fine-grained reactivity (Virtual DOM for React/Preact, signals for Angular, runes for Svelte, etc.) and any component that contains another component has to coordinate with it.
As a result, you can only mix-and-match container components between frameworks with different reactivity workflows by giving up on fine-grained reactivity, blowing away the internals when you cross boundaries between frameworks. (And Shadow DOM makes it harder, not easier, to coordinate workflows between frameworks.)
Shadow DOM sucks at the only thing it's supposed to be for. Please, listen to the wisdom of the crowd here.
> it's self-contained: it brings along its own dependencies, whether that's JavaScript, templates, CSS
> Also, don't do this [...] That just adds HTML bloat to the page, something people with a singular focus on eliminating JavaScript often forget to worry about. To many HTML elements can slow the page to a crawl.
A static JS-less page can handle a lot of HTML elements - "HTML bloat" isn't really a thing unless those HTML elements come with performance-impacting behaviour. Which "self-contained" web-components "bringing along their own dependencies" absolutely will.
> shouldn't require an external framework
If you're "bringing along your own dependencies" & you don't have any external framework to manage those dependencies, you're effectively loading each component instance as a kind of "statically linked" entity, whereby those links are in-memory. That's going to bloat your page enormously in all but the simplest of applications.
You can try to get by with auto-generated selectors for every possible value today, ([background="#FFFFFF"]{background: #FFFFFF}[background="#FFFFFE"]{background: #FFFFFE}...) but just mapping attributes to styles 1:1 does begin to feel like a very lightweight component.
(Note... I'm not convinced this is a great idea... but it could be interesting to mess around with.)
[0] https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/V...
[1] https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/A...
What woud have been a soup of `div` elements with various class names are now more meaningfully named elements like `<top-bar>`, `<chat-container>`, etc. that were mixed and remixed to create all the graphics.
Also no issues regarding performance that we've seen up to this point, which makes sense; browsers are very good and fast at rendering HTML elements (native or custom).
However, it's basically describing the "modifiers" part of BEM, which is a pattern that emerged from structuring CSS. Neither custom element or attributes are needed, even though they might feel different.
If you like that kind of pattern to structure CSS, then combining it with custom CSS properties (often called "variables", example: --block-spacing: 2rem) makes it even more modular. These properties follow the cascade rule.
<div> and <span> are semantically neutral, so I'm not sure what SEO and accessibility challenges custom elements would introduce?
> "shadow DOM — can be used without JavaScript" Yes, shadow DOM can be used without JS, but I was talking about web components.
> "I'm not sure what SEO and accessibility challenges custom elements would introduce?" If you replace standard elements (such as 'p', 'a', 'button', etc) with custom ones it can hurt SEO and accessibility. There are very few reasons to use custom element names and attributes if they are not full web components.
What's the point of using selector 'link-button[size="large"] a {...}' when you could do the same with '.link-button.large a {...}'?
And since that would drive us to <div>, I don't see any value in <div class="swim-lanes"> over <swim-lanes>.
It’s more than just an aesthetic preference
But if you’re not really using web components it’s harmless but it’s a bit odd and pointless.
1. Specificity - swim-line.buttons vs .swin-lines.buttons vs .buttons.swim-lanes. 2. Future pathing - Maybe you don't need a Web Component today, but you might need one tomorrow. 3. Cleaner - <swim-lane /> is just better than <div class="swim-lane" />