# js

* [Toolbox](#toolbox)
* [Frameworks](#frameworks)
* [UI](#ui)
* [Basic](#basic)
  * [text](#text)
  * [export & import](#export--import)
* [the default export can be imported with any name](#the-default-export-can-be-imported-with-any-name)
  * [this](#this)
  * [IIFE (Immediately Invokable Function Expression)](#iife-immediately-invokable-function-expression)
  * [Chrome Cross origin requests](#chrome-cross-origin-requests)
  * [pdf.js](#pdfjs)
* [JQuery](#jquery)
  * [events](#events)
* [JSX](#jsx)
* [MDX](#mdx)

## Toolbox

<https://bun.sh/>

```
powershell -c "irm bun.sh/install.ps1 | iex"
curl -fsSL https://bun.sh/install | bash
```

## Frameworks

* Vue: <https://nuxtjs.org/>
* React: <https://nextjs.org/>

## UI

* byCF: <https://kumo-ui.com/>

## Basic

### text

```
if ("ab"+"c".includes("bc")) { t="_3"; console.log(`t${t}`.replace(/\d/, "").length); } else if (true) {} else { } // Out: 2
```

### export & import

* <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/export>
* <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import>

  ## the default export can be imported with any name

  export default k; // file test.js import anyName from "./test";

### this

<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this>

```
const test = {
  prop: 42,
  func: function() {
    return this.prop;
  },
};
```

### IIFE (Immediately Invokable Function Expression)

```
(function() {
    statements
})();
```

### Chrome Cross origin requests

Cross origin requests are only supported for protocol schemes:\
http, data, chrome, chrome-extension, https.

### pdf.js

<https://github.com/mozilla/pdf.js/tree/master/examples/helloworld>

## JQuery

### events

<http://api.jquery.com/category/events/>

## JSX

an XML-like syntax extension to ECMAScript without any defined semantics: <https://facebook.github.io/jsx/> `const element = <h1>Hello, world!</h1>;`: <https://zh-hans.reactjs.org/docs/introducing-jsx.html>

## MDX

JSX + Markdown: <https://mdxjs.com/docs/what-is-mdx/>


---

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