React's UI State Model vs. Vanilla JavaScript

https://arihantverma.com/posts/2021/07/17/react-ui-state-model-vs-vanilla-js/

by gdad-s-river • 5 years ago

99 168 5 years ago

Spivak2• 5 years ago

The problem with React (or the reason you might want to sometimes choose VanillaJS) is that React's algorithm to apply a DOM diff has to be completely generic. In React your flow will loosely be

    Something happens
    The browser triggers and event and sends it to React
    React calls your code to re-render the world[1]
    React takes the new world order and does a diff
    React calculates what to do go from old -> new and applies

In VanillaJS world you can do way way way better than this with the benefit of knowing how your application works.

    Something happens
    The browser triggers and event and sends it to your handler
    Your handler updates the DOM

It would be nice if in future you could make some promises to React about what happens on an event so React can skip the diffing step and just update the virtual and real DOM directly. And hint hint if you can generate the code to update the DOM directly in the general case too then do you even need the virtual DOM? Svelte is doing really cool work in this space.

[1] componentDidUpdate helps but same diff

bookofsand2• 5 years ago

The beauty of the virtual DOM is that it relies on pure view functions: given this props+state input, this is how the DOM looks like. Generating DOM fragments on update is possible, but naively done it will quickly get out of sync with the DOM view function. Curious about 'really cool work' in this space!

vosper• 5 years ago

Generating DOM fragments on update is possible, but naively done it will quickly get out of sync with the DOM view function. Curious about 'really cool work' in this space!

This is what Svelte's doing, as I understand it: letting you think like you're writing React ("when in this state, the world should look like this") but avoiding the (greatly overstated, IMO) overhead of the virtual DOM by translating the changes into direct DOM updates in a complilation step.

eyelidlessness2• 5 years ago

Like I did in another subthread I’d suggest looking at SolidJS. It’s philosophically similar to React for rendering, uses JSX, and at least as “pure”. It has reactive APIs similar in use to React hooks (neither of which are pure), but compiles to DOM.

cjonas• 5 years ago

The whole point of react is to avoid the stateful nightmare created by the latter approach. When given Y, render X.

I'm glad it's not easy to escape the paradigm.

I know there are cases where it's needed but it's rare (at least in my line of work).

Spivak2• 5 years ago

Of course! The takeaway is that in the future it would be nice if you could have the best of both worlds by being able to compile some DOM transformations ahead of time and/or have React observe and JIT them so you can bypass React's machinery most of the time while getting to pretend its there. It will feel like a re-render but it's actually just a direct DOM manipulation behind the scenes. That's Svelte in a nutshell.

rubicon33• 5 years ago

The whole point of react is to avoid the stateful nightmare created by the latter approach.

I found this ironic, as I have never in my life had more struggles with state, than when working with react native. Seriously, the amount of times something didn't update, or was updating way too many times, is countless. It's so easy to shoot yourself in the foot. Imperative native programing, almost never have this issue.

eyelidlessness2• 5 years ago

SolidJS is doing this at the compiler level. JSX components become DOM nodes and its underlying reactive primitives.

bayesian_horse14• 5 years ago

The point is that in real applications it is really hard to get the update logic straight.

The React haters here seem to think that is easy. But most of the popular frameworks/libraries use a virtual DOM in some way or another. And Svelte also automates handling the updating. Maybe it's not so easy after all, if smart people have spent decades trying to find alternatives.

username912• 5 years ago

It seems deceptive to me to compare using createElement etc. to JSX, rather than using innerHTML, or a <template>.

RodgerTheGreat2• 5 years ago

likewise, using an unnecessarily repetitive style in the "vanilla" version and using a few compact ternaries in the "react" version.

you can get pretty darn close to the react version of this example using vanilla js.

reilly3000• 5 years ago

I think that was mostly for illustrative purposes. Most websites aren’t built like that, but it helps show how attributes on DOM objects can be manipulated before throwing the reader into React state concepts.

username912• 5 years ago

That's a fair point!

QuadrupleA3• 5 years ago

Ugh, this is massively overcomplicating the vanilla js case.

Just put the checkbox html & css on the page. Write a function that updates the label based on checked state. Call it on input/change events.

It's like 3 lines of js.

React.js people always invent this vanilla js / jQuery strawman that's so complicated and spaghetti that no mortal can possibly understand it.

It's total BS. You can write succinct maintainable code without a 100 lb framework.

savanaly• 5 years ago

It's all about scaling of complexity and number of engineers working on the project. No doubt hand rolled js is better when you only have to do the one thing you mentioned and you're the only person who has to read or write the code.

What happens when it's one of hundreds of checkboxes on the site? When they all do slightly different things depending on user sku, product page, file type, file permissions, god knows what else. And when one experiment flag is on or how about this other one? Then i18n? Then what about the fact that after you write this line countless other engineers will see and modify it in the future, it's not just you writing and maintaining it? These are the problems that my company (and, I assume, Publicis Sapient with 20,000 employees according to Google) have to consider when choosing whether to hand roll JS or use a framework.

simonw5• 5 years ago

Then you can switch to something like React. But most projects won't ever get close to the level of complexity you are describing.

Meanwhile I have seen SO MANY sites that use full React for a contact form with two fields on it.

QuadrupleA3• 5 years ago

Everything a programmer does is "hand rolled" whether it's JS or JSX.

You'll still have to tackle those complex requirements and come up with a good design that organizes things and makes them manageable, whether you're using React and JS or just JS.

To say that a good design is just impossible with JS or that no other engineers could possibly understand the resulting code seems absurd.

Javascript is a Turing-complete language. It gives you a lot of design options. Your poor engineers will have to learn it to use React anyway so why would vanilla js necessarily be worse than js plus a giant framework?

errantspark• 5 years ago

Yup. React is a tool so that thousands of people can speak the same language about a big codebase. That's what it's for, that's the only thing it's (arguably) good at. If you want to pretend otherwise you're left to these sorts of mental gymnastics to make the evidence fit your assumptions.

atatatat• 5 years ago

How does it achieve this?/aim to achieve this?

vpj3• 5 years ago

This is true. We recently re-wrote everything in plain javascript from react, and it didn't increase the lines of code.

The vanilla code was much easier to maintain too. React comes in your way when things get complicated and the work arounds produce really messy code.

Edit:

Project (GitHub): https://github.com/labmlai/labml/tree/master/app

It's a mobile/web app to monitor machine learning experiment.

bayesian_horse14• 5 years ago

Without context like what this application does or how many lines of code you are talking about, this means exactly nothing...

Also there is nobody stopping you from writing extremely messy React applications...

habibur2• 5 years ago

This gives more information than any other analytical comment. Someone who has used both to build the same application and can compare the experience between both.

It's not the final say. Just a strong signal among many others.

bayesian_horse14• 5 years ago

If you need to achieve the same functionality and maintainability without React (or some other external library), then by definition you somehow have to reimplement much of it yourself. And no, React isn't all that big in terms of functionality or size.

What are the chances that you are arriving at a solution that is better than React? That other engineers have no trouble understanding and maintaining? You'd have to invent new concepts, or at least call them differently, to not copy React's (or any other framerwork's) concepts or ideas. That would make it harder for other people to understand the code.

seer• 5 years ago

Well react itself is just the virtual diff algo really.

How to change this page to this other page as fast as possible, if you don’t know or don’t care to know that other page.

That second qualifier is really important. As long as you have 2-10 screens and know the transitions by heart, nothing stopping you from hand rolling js. But once you start adding states things get tricky really fast, as transitions grow exponentially.

I’ve built some very complicated apps with vanilla js back in the day, and we had ways of dealing with things like that. We called it “reloading the page” where you start from 0 with your state. Kinda like restarting windows to fix it, rather than figuring out whats wrong.

And you could get quite far that way. 37signal’s basecamp was like that - an html app with vanilla js sprinkled throughout. Worked great.

But there is a limit in complexity. JS and html are great for building websites, but if you want to build an actual application, you need to be really clever and accept a lot of limitations. React just lifts the ceiling of what you can do, without being all to complicated.

And you can use the technics of react without react itself too, once you understand what it is all about - https://github.com/ivank/vanilla-teuxdeux

kreetx3• 5 years ago

Why do the virtual dom thing at all? Just remember the locations you need to update and update only them, like svelte or lit-html.

schwartzworld2• 5 years ago

"I hate people advocating for a tool by bringing up the problem it was used to solve. Just keep your app so simple that you don't need the tool."

A better solution is to emulate the react strategy. Create a state object, on user input you can rewrite sections DOM based on the state. You probably don't need React's diffing algorithm until you run into performance problems. Then you have to limit which parts of the Dom you update to keep it snappy. Then you might as well just use react.

edem3• 5 years ago

Then you end up rewriting a buggy under-performing version of React. No, thanks. If size is really a concern use Preact.

cxr• 5 years ago

"I hate people advocating for a tool by bringing up the problem it was used to solve. Just keep your app so simple that you don't need the tool."

Casually dismissing others by strawmanning them with fake quotes is against the rules. Even outside of that, it's just generally the kind of thing that is neither respectful or respectable. Please don't do it.

benbristow6• 5 years ago

And so you just recreate React but worse and make it harder to onboard new developers and can't use any of the great React libraries/components already created by the community.

stephenr• 5 years ago

The example as shown doesn’t even need JavaScript. It could be a few lines of css.

leephillips• 5 years ago

And that would be even shorter than the React version.

Waterluvian• 5 years ago

For primitive apps or anything that’s very straightforward like CRUD forms and tables, vanilla works great and should be encouraged.

Anything moderately complex gets really painful when you’re storing state in all your HTML elements.

A big part of React is to abstract away the horribleness of trying to prevent unnecessary, quite expensive interactions with the DOM.

That’s why a lot of comparison examples miss the point and facilitate poor discussion.

benbristow6• 5 years ago

Cool.

Project Manager: Now add 3 checkboxes, one being 'N/A' and when you select N/A the other checkboxes are disabled and unchecked. And update the labels, and have additional form sections showing depending on which checkbox is displaying.

Probably not that difficult, and probably a bad example, but with React/Vue/etc. it's a lot easier to deal with complex states than manually manipulating the DOM.

From experience trying to be clever and anti-framework ends up just creating another framework that's worse in every imaginable way.

edem3• 5 years ago

And they also end up with a lot of useless framework knowledge they'll never use again after the project goes up in flames.

marcosdumay2• 5 years ago

Hum... Your new function reads all the checks, calculate the new values and enabled conditions, and applies them. It's called by the onChange of all of the relevant elements.

Reactive frameworks do make your life simpler (at least once you pay for the large one time cost of using them), but the change isn't enormous.

mattgreenrocks4• 5 years ago

clever

Virtual DOM qualifies as clever in my book. :)

Better question to ask is why so many libraries/frameworks proliferate in webdev and not as much in native apps. JS is a suitably powerful language these days.

Also, the attitude of “just use jQuery like everyone else” (paraphrasing the last paragraph and substituting for React) would have precluded the development of React.

_nub3• 5 years ago

is that how react was invented?

edem3• 5 years ago

You (and most commenters on this branch) forget the most important thing: there are bazillions of libraries that work with react so I don't have to produce all that untested vanilla code. I only have to wire them together in a way I see fit and then I can jump on the next project. Also: good luck finding a person who would forego using and maintaining their easy-to-market React skills.

acdha3• 5 years ago

None of which is specific to React, as decades of history shows. One reason that history is worth paying attention to is that it confirms that you’ll be spending a lot of time managing dependencies, testing breaking upgrades, and working with upstream maintainers to fix problems and add features. It’s still a net win but there’s a real cost which is easy to ignore until you count the number of FTE weeks which went into keeping a project building and secure.

brundolf• 5 years ago

You're right that this doesn't represent the way a vanilla JS UI would ever actually be written in practice (even calling it a "vanilla JS UI" instead of an "html UI" points directly at the problem)

But:

1) Even though the web-specific example is contrived, it's a good demonstration/explanation of what people mean generally by declarative vs imperative

2) I don't want to wade into the tired argument, but classic HTML + minimal hand-written JS doesn't scale beyond a certain point. If it did, everyone would still be doing things that way

geenat• 5 years ago

https://htmx.org/

naasking• 5 years ago

I've been meaning to try this as it looks promising.

EugeneOZ• 5 years ago

Why trying to explain “declarative vs imperative” if both examples are totally imperative?

At least vanilla js version doesn't re-render the whole component.

simonw5• 5 years ago

    var checkbox = document.querySelector(
        "input[type=checkbox]"
    ), container = document.querySelector(
        "#wrapper"
    );
    checkbox.addEventListener("change", () => {
        if (checkbox.checked) {
            container.classList.add("checked");
        } else {
            container.classList.remove("checked");
        }
    });

Then use CSS to show or hide the message inside the container based on if it has class "checked" or not.

You can get a whole lot done with very little code if you learn to take advantage of the three-legged stool of HTML, CSS and JavaScript.

SeriousM• 5 years ago

That's the right way of separation of concerns: handle states with code, look/layout with css.

nsonha5• 5 years ago

funny you should say that, because there is no explicit state here, what happens when there are 10 checkboxes? Just read `.checked` in the dom element?

pgcj_poster• 5 years ago

There's already a :checked selector, so you don't really need JavaScript at all in this example.

  <input type="checkbox" id="discount">
  <label for="discount"></label>
  <style>
    #discount + label:before {
      content: "Click me to apply fake discount!";
    }
    #discount:checked + label:before {
      content: "Click on me to remove fake discount";
    }
    #discount + label:after {
      content: "You have not availed discount";
      display: block;
    }
    #discount:checked + label:after {
      content: "Discount Availed!";
    }
  </style>

simonw5• 5 years ago

Even better!

RodgerTheGreat2• 5 years ago

or save a conditional:

    container.classList.toggle('checked',checkbox.checked)

simonw5• 5 years ago

I forgot about .toggle(), that's definitely neater.

beebeepka• 5 years ago

Over engineering things is truly one of the biggest problems in our industry. It's been years and react still seems like an organized religious community to me. With many, many preachers.

Reminds me of all the "yaml is better than XML/JSON" examples where everything is carefully formatted in a way that make no sense unless you are trying to prove a point.

Part of me think we should just ignore html and just render everything using webgl/webvulkan/whatever instead of fighting the browser's flow. We're not there yet but things have been moving in that direction because it kind of makes sense

t0astbread• 5 years ago

What about accessibility? As far as I know canvases don't offer ways to expose the same semantic information about their contents as the DOM.

oblak• 5 years ago

Yeah, they don't but perhaps the necessary meta could be generated as things are being rendered. It's certainly possible, though I haven't done any actual work on accessibility tools myself. I guess it's not a trivial problem to solve without breaking things here and there, otherwise someone would've done it already. Not impossible I'd think

gherkinnn4• 5 years ago

Reimplementing everything the browser does within canvas. Speaking of over-engineering. Flutter 2, for example, can't even get scrolling right [0].

0 - https://gallery.flutter.dev/

atirip3• 5 years ago

Oh please, if you want to compare, use modern vanilla too...

  <!doctype html>
  <body>
  <custom-element></custom-element>

  <script>
   const CHECKBOX_ID = "my-checkbox";
   const defaultLabelContent = "Toggle me, you newbies";
   const beforeDiscountText = "You have not availabled discount";
   const afterDiscountText = "Discount Availed!";
   const beforeLabelText = "Click on me to remove fake discount"
   const afterLabelText = "Click me to apply fake discount!"

   const state = new WeakMap();

   class CustomElement extends HTMLElement {

    connectedCallback() {
     this.render();
     this.shadowRoot.addEventListener('change', (event) => {
      state.set(this, event.target.checked);     
      this.render();
     })
    }
 
    constructor() {
     super();
     this.attachShadow({ mode: 'open' });
    }

   
    render() {
     let isChecked = state.get(this);
     const discountText = isChecked
      ? afterDiscountText
      : beforeDiscountText;
       const labelText = isChecked
      ? beforeLabelText
      : afterLabelText;
     this.shadowRoot.innerHTML = `
      <input
       ${isChecked ? 'checked ' : ''}
       type="checkbox"
       id=${CHECKBOX_ID}
      >
      <label for=${CHECKBOX_ID}>
       ${labelText}
      </label>
      <div>${discountText}</div>
     `;
    }
   }

   customElements.define('custom-element', CustomElement);

  </script>

montenegrohugo• 5 years ago

Codepen for this:

https://codepen.io/uwwgo/pen/GRmEKJz

(nothing revolutionary, does the exact same thing.)

infensus• 5 years ago

Well, technically it's not an equivalent as this would recreate dom nodes on every render

atirip3• 5 years ago

This was just taking the final React code in the article and rewriting it in vanilla as close as possible.

Your comment is fully correct, but I would like to point out:

- with such a tiny DOM to rerender, it is equivalent, probably even faster

- custom element encapsulates DOM and it is fairly trivial and extremely fast to pick DOM (like you can even use id's everywhere) in the 'old jquery' way, with simple library functions

- updating DOM with simple render() call is way more elegant, but if you keep custom elements DOM small (and one should), this way is not that bad at all

Like this:

  <!doctype html>
  <body>
  <custom-element></custom-element>

  <script>
   const CHECKBOX_ID = "my-checkbox";
   const defaultLabelContent = "Toggle me, you newbies";
   const beforeDiscountText = "You have not availabled discount";
   const afterDiscountText = "Discount Availed!";
   const beforeLabelText = "Click on me to remove fake discount"
   const afterLabelText = "Click me to apply fake discount!"

   const state = new WeakMap();

   // 'library' code
   function qs(selector) {
    return this.shadowRoot.querySelector(selector);
   }

   function getElem(nodeOrSelector) {
    return nodeOrSelector === String(nodeOrSelector) ? qs.call(this, nodeOrSelector) : nodeOrSelector;
   }
     
   function replaceText(nodeOrSelector, text) {
    let elem = getElem.call(this, nodeOrSelector);
    if (elem) elem.textContent = text;
   }

   function updateAttribute(nodeOrSelector, name, value = '') {
    let elem = getElem.call(this, nodeOrSelector);
    if (elem) elem[(value ? 'set' : 'remove') + 'Attribute'](name, value);
   }
   // end of 'library' code

   class CustomElement extends HTMLElement {

    connectedCallback() {
     this.attachShadow({ mode: 'open' });
     this.shadowRoot.innerHTML = `
      <input type="checkbox" id=${CHECKBOX_ID}>
      <label for=${CHECKBOX_ID}></label>
      <div></div>
     `;
     this.shadowRoot.addEventListener('change', (event) => {
      state.set(this, event.target.checked);     
      this.update();
     })
     this.update();
    }
 
   
    update() {
     let isChecked = state.get(this);
     updateAttribute.call(this, 'input', 'checked', isChecked);
     replaceText.call(this, 'label', isChecked ? beforeLabelText : afterLabelText);
     replaceText.call(this, 'div', isChecked ? afterDiscountText : beforeDiscountText);
    }
   }

   customElements.define('custom-element', CustomElement);

  </script>

peanut_worm• 5 years ago

What does storing the state as a WeakMap do here?

Ndymium2• 5 years ago

If the custom DOM element is deleted, then its entry in the map will also be deleted. Otherwise it would hang around in the Map forever (unless manually deleted in a lifecycle callback).

atirip3• 5 years ago

I initially just mimicked the React version into Vanilla, so this was a show-off how to do that somewhat exactly the same way. But in this particular case it serves no meaning, we can always read 'checked' from DOM.

megous• 5 years ago

With react you've just moved your imperative code from REST->DOM manipulation to REST->local state manipulation and local state -> DOM mapping.

You have to invent some elaborate local state schema and then map it to DOM, instead of keeping part of the state implicitly stored in DOM, where it makes sense.

You can assign your data directly to DOM node objects. Say `el.yourData = todo_item`. And then let the order and list of items be kept implicitly in DOM, so you can do obvious things like remove nodes using `.remove()` reorder them via DnD, and whenever you need the list as data, you just querySelectorAll('.item').map(el => el.yourData) and you have your list. All quite straightforward.

You can also do context dependent things by being able to travel up to the ancestors via parentNode.

Declarative frameworks like react make simple things like this painful in comparison.

chmod7752• 5 years ago

This is just an ad.

I wish software developers would be more honest about their tools, weighing their pros and cons, instead of thinking up contrived 'examples' that paint them in the best possible light.

Every library/tool/framework will make you think "well, this sucks" at some point. So be honest.

acdha3• 5 years ago

I tend to see the problem as the point where people stop thinking of them as tools and more part of their self-identity. If learning how to use React makes you more productive, it’s only reasonable to use it on your next project. The problem starts when you start thinking “using React makes me a Real Programmer™ like the cool kids at Facebook” and that turns every discussion into a tribal loyalty test.

ipnon2• 5 years ago

The paucity of Facebook veterans does more in my mind to explain the popularity of React than its UI state model. React is popular because it's popular because it's popular ...

simondw• 5 years ago

Do you perhaps mean abundance instead of paucity?

ipnon2• 5 years ago

No, they get instantly hired, then they say nothing but "React ... React ... React." And the rest of the team goes, "wow they really do things differently in Menlo Park!"

hajile3• 5 years ago

React wasn't always popular...

I remember using jQuery, Backbone/underscore, handlebars, knockout, Angular 1, Enyo, Ember, and probably a couple others. Angular in particular had like 70% market share among major frameworks and almost all the libraries didn't support React.

React took over because it was head and shoulders better than everything that went before and taking days to learn instead of weeks or even months.

The reason nothing has taken over since is because we've reached the point where they aren't good enough to justify throwing away all the existing library support.

GrumpyNl• 5 years ago

Great example how to over complicate something so simple as state of a checkbox.

Tomuus• 5 years ago

I think this article skips over many nuances of the declarative model.

For a real "ground up" approach of explaining those I'd recommend this article series: https://acko.net/blog/climbing-mt-effect/

gdad-s-river• 5 years ago

Thanks for the recommendation! Read through all the three articles. Learnt a lot. Even though some of the things written in a way that were 'handwaving' as the author writes himself, and I couldn't understand everything ( I'll keep revisiting ) I'd never thought about declarative model enabling using O(n) code instead of O(n^2) when state in the application increases, and some of the other things he talks about. I've linked these articles series as a first thing in my blog post.

jazzyjackson• 5 years ago

So no one’s going to mention the css sibling selector? You don’t need JavaScript to reveal elements based on the state of a checkbox.

atum47• 5 years ago

Let's not forget that if your main goal is to have an element that is clickable and update it's label you can write a function for that or even create your own component that does just that.

Your heard me correctly, you can create components with JavaScript without the aide of a framework.

mcintyre1994• 5 years ago

Why would you use JavaScript to write your HTML elements in the vanilla case? Surely you could just have a plain HTML checkbox and your default text, and then add an event handler to update the text when the checkbox changes? That’s how React with something like NextJS behaves, vanilla JS you get it for free unless you decide to use JS to write your elements like this.

zurgax• 5 years ago

Toggling the checkbox in the completed vanilla example halfway down the page didn't change its subtitle text for me on Safari - instead it updated the subtitle in the example at the very top of the page. Does it find the first matching element on the page and update it? (I don't know JS, DOM)

lucideer• 5 years ago

I love React. I love the elegance and flexibility of it's architecture, and the power of it's modularity. There are so many really great reasons to use React.

This article is absolute nonsense from start to finish. What amounts to basically "lying" about the complexity of vanilla JS actually ends up mainly just doing a massive disservice to React which shouldn't need false comparisons to show it's benefits.

Maybe they're just being disengenuous but I got the distinct impression from many of the examples that the author doesn't actually know vanilla JS at all.

claviska• 5 years ago

This is the impression I got. The first half of the vanilla example is imperatively creating DOM elements, assigning attributes, and inserting them into an “app” <div>. My guess is the author learned React first and never considered that HTML can be written as (gasp) HTML!

bob10292• 5 years ago

To me, the more fundamental problem is the fact that we spread state across multiple computers.

If you only mutate state on the server and simply send views back down to the clients, nearly all of "modern" web development practices can be safely ignored.

Clearly, there are difficult engineering challenges with the approach of "all state on the server all the time", but anything worthwhile is never easy. Down this path you might not obtain Netflix-tier webscale directly out of the box, but that doesn't mean we throw our hands up and have all our clients drown in multiple megabytes of angular11+ dependency trash either.

How many internet users are more than 50ms away from a Cloudflare/Microsoft/Google/Netflix CDN in 2021? How many cores can you get in a 1U server now? Distributed state machines for client UIs have been a massive mistake.

ngrilly• 5 years ago

I mostly agree, but having used Linear.app which has a crazy good and fast UI based on a local database synced with their cloud database, I'm not sure anymore: https://youtu.be/WxK11RsLqp4?t=2170.

I think it's important to define early in a project if the app is "cloud-based" or "local-based". If it's cloud-based, then only the server mutates state and sends views to the clients, as you wrote. Everything is simple. If it's local-based, then all data are available locally and mutated locally. The cloud is only used as mirror/backup and can support for some advanced features like full-text search. That's also a very clear architecture. That's how Linear works.

Things become hairy and unnecessarily complex when no clear choice is made between those two options, then it's not clear where the state is.

dehrmann• 5 years ago

there are difficult engineering challenges with the approach of "all state on the server all the time"

There are real world challenges. There's no internet access on the NYC subway. Latency can spike for no apparent reason. Making a webapp a dumb client really only works for wired connections on an intranet.

bob10292• 5 years ago

... but anything worthwhile is never easy.

When I was working in South Korea, their subway system had excellent reception to cellular and even satellite TV networks. They explicitly engineered a solution to this problem in direct, first order terms.

This is precisely the type of approach we should be taking in my opinion. Make the networks robust, not the client-facing web apps. We are spending engineering resources in largely the wrong places.

This would be like arguing for a car that can hover, but only for an ambiguous/non-specific amount of time, simply because the roads are occasionally total shit.

gherkinnn4• 5 years ago

To me, the more fundamental problem is the fact that we spread state across multiple computers.

I completely agree. Sharing a layer of an application between client and server is a nightmare and will fly in your face.

That said, it is possible to cleanly handle more involved interaction on the FE and have a clean separation of responsibilities. When well done, the results are very snappy and robust. Of course, it isn't always necessary, and most RoR applications beat that 5mb Angular behemoth.

game_the0ry• 5 years ago

I get the impression that the author is so into the react way of doing things that they can't seem to comprehend and write JS in a non-react (vanilla) way, thus polluting the author's approach to writing vanilla JS.

If anything, this article is an example of how you need to write and truly understand vanilla JS (and learn form your mistakes) before you can appreciate and understand what react had to offer when it first came out.

I might have to write a counter blog post just to balance this out...SMH.

eatonphil2• 5 years ago

Showing the difference between markup/scripting a single static element is pretty different from applications where you have to display lists of things with other lists of things inside. If you only have static elements then just writing it in HTML and making it dynamic with JavaScript is fine.

But once you have to display lists of stuff with lists of other stuff inside you basically need a template library otherwise you're going to be doing some pretty weird DOM manipulation to copy sections of elements.

So a comparison that might resonate better with folks here might be to have a pure JS TODO app with a comment section in each list item. It becomes harder to express in pure HTML. You'll want some template library to keep it maintainable.

dorfsmay• 5 years ago

Template on the server?

If your lists are long enough, you probably want to split what you can actually display from the rest of the list, because even today updating the DOM with thousands of nodes is expensive. And doing seems to be easier and less chatty to do on the front-end I think.

eatonphil2• 5 years ago

Sure templates on the server are fine too I just mean that the comparison is more compelling when describing the things that prompt templates in the first place (whether on the server or frontend).

aszen• 5 years ago

While this article doesn't do a good job of showing the benefits of state model, I still think it's a great way to build ui. Thinking of ui as derived state from your application model really helps in scaling ui applications reliably. Unfortunately react is not the best example of this approach. I would say try out elm or some of the clojurescript frameworks like reframe to truly grasp ui as application state

specialist• 5 years ago

Huh. This OC frames the debate as imperative vs declarative. Is that right? It just now occurs to me that React vs vanilla is another iteration of the MVC debate.

I lived thru the Java AWT to Swing transition. One of Swing's Big Ideas was for every component (aka view & controller) to be backed by a separate model, finally mainstreaming the MVC design pattern.

Then of course all the web frameworks got nutty over MVC.

My only takeaway from the many, many MVC debates is that the only way to win is to not play.

pictur• 5 years ago

Sometimes I think people don't know for what purpose projects like React are developed. Or they act like they don't know. Please stop praising your horrible code written in vanilla javascript.

gherkinnn4• 5 years ago

I like most of React and am strongly against writing anything akin to an SPA in vanilla JS. (Whether or not an SPA is the right approach is debatable but besides the point)

And yet this article is disingenuous. The OPs target can be achieved using CSS alone. In fact, quite a lot of things can be done quite well in vanilla JS and CSS.

This works well to some degree. Then I found it to fall apart.

- Those BE devs now forced to write FE in React|Vue|* and hate it so much that they've never learned it, won't learn a vanilla stack either. Especially not CSS. That's just for colours. Or something.

- Most vanilla approaches I worked on relied heavily on the correct ordering of HTML elements with the correct classes for something to work. There's little to no encapsulation. Only copy and paste. It's also immensely brittle.

- You can add some simple encapsulation, but the easier way is to brute force some imperative mess. Close ticket. Open next. Velocity is high.

- The next step is to build your own framework. But chances are it will be worse than any 3rd party solution.

- A huge advantage of 3rd party libs is that there's zero chance of some ticket specific code to erroneously make its way in to the framework. Silos aren't always bad.

- Onboarding new devs is hard. There's probably no resources at hand.

- At this point you've tied yourself in to knots and the actual problem, your product, isn't even close to being solved.

It takes less than an hour to have a fast React|Vue|* application off the ground. Everything you need to build the product is in place. And with some care, it will remain fast. Alternatively, Ruby on Rails and friends work just as well.

However, wasting endless hours reinventing a worse wheel is unproductive.

React's UI State Model vs. Vanilla JavaScript

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