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Helitha Rupasinghe
Helitha Rupasinghe

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Explain JSX like I'm five.

#discuss #explainlikeimfive #javascript #beginners

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posandu profile image
Posandu • • Edited

JSX is just fancy HTML (With some rules) that compiles to pure JavaScript. So if you write something like this:

 <div>
    <h1>Hello World</h1>
 </div>
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It will compile to something like this:

React.createElement("div", null, React.createElement("h1", null, "Hello World"));
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So now you can generate HTML with JavaScript. This is the basic idea behind JSX.

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hr21don profile image
Helitha Rupasinghe •

Great example! 👏

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codesimple profile image
code-simple •

👏Welldone

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andrewbaisden profile image
Andrew Baisden •

Some of these answers are too complex for a five year old to understand 😂

My attempt... JSX is like the instructions you get inside a box of lego that shows you how to build stuff. The lego box is your container and the blocks are you being creative and building something with it.

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hr21don profile image
Helitha Rupasinghe •

Thank you for posting this! 👍

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pengeszikra profile image
Peter Vivo • • Edited

Fo me JSX is a first selling pont of react (and nextjs). Because I can create any HTML releated stuffs at no time with simple js (ts) function, without need to know any template language syntax. I can use any js controll sequence for put together the view.

JSX also give good abstraction for view declaration.

// nextjs also can declare head elements

const FooGameFrame = () => {
  const [state, dispatch] = useSagaReducer(mainSaga, gameReducer, initialState);
  const army = getDispatchedActions(getActionsLookup(), dispatch);
  const {game, hero} = state;

  return (
    <section className='portal-root m-2'>
      <MobilFrame>
        <Head>
          <title>Foo Game</title>
          <meta name="viewport" content="initial-scale=1.0, width=device-width" />
          <link rel="manifest" href="manifest.json"></link>
        </Head>

        {game === GameMode.ROLL_CHARACTER && <CreateHero state={state} army={army} />}
        {game === GameMode.ADVENTURE_ON_MAP && <SingleAdventure state={state} army={army} />}
        {game === GameMode.BLOG && <Blog name={hero?.name} avatar={hero?.avatar} />}
      </MobilFrame>
      {game === GameMode.ADVENTURE_ON_MAP && <CombatZone state={state} army={army} />}
    </section>
  );
};
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jahid6597 profile image
MD. JAHID HOSSAIN •

Imagine you're playing with your building blocks. You have different blocks of different colors and shapes, and you can use them to build anything you want.

Now, imagine you want to build a house. You can use your blocks to create the walls, the roof, the door, and the windows.

In the same way, when people want to build a web page, they use HTML to create the different parts of the page, like the headings, paragraphs, images, and links. But sometimes, they also want to add more dynamic and interactive elements, like a button that changes color when you click on it.

That's where JSX comes in. JSX is like a special type of building block that helps people create these dynamic elements. It looks a lot like HTML, but it also allows people to add JavaScript code to create more complex and interactive elements.

So, just like you use your building blocks to create a house, people use HTML and JSX to create web pages with all kinds of different elements that work together to create a fun and interactive experience.

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ben profile image
Ben Halpern •

Nice reply

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matijanovosel profile image
Matija Novosel • • Edited

JSX is a combination of HTML and Javascript to put it simply, or as the official React site says: "a syntax extension of Javascript". It offers the functionality of writing Javascript expressions inside HTML elements which is then processed to create the UI.

e.g. this...

const navBar = (<nav className="bg-yellow"> Home </nav>);
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... gets converted into:

const navBar = React.createElement("nav", { className: "bg-yellow" },  "Home");
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hr21don profile image
Helitha Rupasinghe •

Thank you for sharing!

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lexlohr profile image
Alex Lohr •

JS is a language describing logic and interaction. HTML is a language describing content, based on XML, which is meant to describe arbitrary data.

JSX, a shorthand for JS+XML, is these two languages put together into one. In JS, you can use numbers, strings, etc, but HTML code would cause errors. In JSX, HTML Code becomes a valid value that represents the actual HTML.

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jonrandy profile image
Jon Randy 🎖️ •

An abomination

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hr21don profile image
Helitha Rupasinghe •

Very informative! 👍

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hanufu profile image
Eduardo Ribeiro •

lol

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jonrandy profile image
Jon Randy 🎖️ •

👍

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codingjlu profile image
codingjlu •

JSX allows you to write HTML in JavaScript and is treated as a value, which is then compiled to JavaScript in which a function is called to represent the element specified. This code is usually then used in the browser to create virtual DOMs.

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dylanwatsonsoftware profile image
Dylan Watson •

To a 5 year old? That's tough! Ok here goes:

JSX helps us tell the computer where all parts of a web page should go and what they will look like. It also lets us easily give the computer the information we want to show on the web page.

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hr21don profile image
Helitha Rupasinghe •

Amazing!

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allisongarner profile image
AllisonGarner •

JSX stands for JavaScript XML. It is mostly used with React to describe what the UI should look like.

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hr21don profile image
Helitha Rupasinghe •

Love this! 🔥

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icyjoseph profile image
Joseph •

JSX is an extension to the JavaScript language, which aims to give a way to fully represent named objects, with their attributes, and their role in a hierarchy, all in one go.

It is not HTML, strictly speaking, but it does carry a lot of similarities, and, perhaps, even creates certain expectations that are not true.

Since JSX just represents an object, we can use that information to do a variety of things, from CLIs, Word Documents, Videos, Web UI, Mobile UI, etc., I for once have used it to make, albeit useless, forward calculation networks, that then I blend with React to render the results to a web UI.

It is pretty cool what one can achieve with JSX syntax.

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zhouyg profile image
zhou-yg •

JSX is a syntax candy created by React

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yosipmikecolin profile image
Yosip Mike Colin •

Se denomina JSX a la combinación de HTML y JS para dar lugar a un código mucho mas compacto y elegante.

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hr21don profile image
Helitha Rupasinghe •

bien dicho hermano

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jamescurran profile image
James Curran •

JSX takes HTML, a simple straightforward way to describe formatted text, and made it verbose, complex and confusing.

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wudixer profile image
Steffen Lips • • Edited

JSX or TSX (for TypeScript) can be used in pure Javascript/TypeScript. It works perfectly without React.
It eases the creation of dynamic code e.g. filling a table with new rows

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