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Comment by _heimdall | Hacker News Reader

That approach passes values in JS rather than the DOM, right? I read the go comment as talking specifically about DOM attributes which can only be strings (well, you can have boolean attributes as well).

Web components can be passed objects in JS, but its news to me if that is available in HTML.

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Yes, this is what I meant. Because you want to listen to attribute changes. Anyway, I was saying it's a good thing. I've built entire complex apps where I pass everything via HTML element attributes; it has made me think about architecture and separation-of-concerns in a specific way which has been really good in terms of increasing transparancy/observability and keeping the code simple.

Simple interfaces are critical for good architecture. Forcing everything to be a string, forces pass-by-value and forces minimal communication between components. You get maximum separation of concerns; high cohesion, loose coupling.

I know exactly what inputs each component is dealing with by just looking at the HTML. This is incredibly useful... And components can output stuff by dispatching events on themselves (with bubbling for important events which may potentially affect higher level components).

I generally think the reflex to try to pass an object to an attribute on an element is a code-smell that the element hasn't been properly decomposed into sub-components. In those cases, I look more to adding child elements to represent those objects as an HTML serialization of the object.

Wow. Yes. Great comment. So glad to come across someone else who fully gets it. Components should 'communicate' with each other. If you start passing elaborate structures, this is getting into the realm of micromanagement, not 'communication'. It means your concerns aren't properly separated.

This is not a new theory. Alan Kay, who invented OOP has been saying such things for decades. People got totally the wrong idea about OOP by focusing on mechanisms to allow passing complex structures to each other. That was never the point.

Imagine if you worked with other people towards some goal and instead of talking to each other and separating responsibilities, ready-made, complex parts would just come out of people's mouths and everyone tried to make each others' parts fit together as an afterthought... Or imagine trying to catch a taxi and you bring a steering wheel and a tank of petrol with you to give to the taxi driver. It's absurd, obviously so, but that's what a lot of people have been doing with code.

If you really need the ability to pass complex objects via an HTML attribute, you can use the same thing we used in the old jQuery and Knockout days: JSON.parse().

    this.someProperty = JSON.parse(this.getAttribute('some-attribute'))

Neither can react

I didn't say it can, I never actually mentioned react at all here.

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