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@dypsilon
dypsilon / frontendDevlopmentBookmarks.md
Last active April 20, 2025 23:00
A badass list of frontend development resources I collected over time.
@paulirish
paulirish / what-forces-layout.md
Last active April 28, 2025 06:24
What forces layout/reflow. The comprehensive list.

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics
  • elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
@zmts
zmts / tokens.md
Last active April 27, 2025 21:01
Про токены, JSON Web Tokens (JWT), аутентификацию и авторизацию. Token-Based Authentication

Про токены, JSON Web Tokens (JWT), аутентификацию и авторизацию. Token-Based Authentication

Last major update: 25.08.2020

  • Что такое авторизация/аутентификация
  • Где хранить токены
  • Как ставить куки ?
  • Процесс логина
  • Процесс рефреш токенов
  • Кража токенов/Механизм контроля токенов
@faressoft
faressoft / dom_performance_reflow_repaint.md
Last active February 10, 2025 17:21
DOM Performance (Reflow & Repaint) (Summary)

DOM Performance

Rendering

  • How the browser renders the document
    • Receives the data (bytes) from the server.
    • Parses and converts into tokens (<, TagName, Attribute, AttributeValue, >).
    • Turns tokens into nodes.
    • Turns nodes into the DOM tree.
  • Builds CSSOM tree from the css rules.
/**
* Event loop.
*
* Read details here:
* http://dmitrysoshnikov.com/ecmascript/javascript-the-core-2nd-edition/#job
*
* by Dmitry Soshnikov <[email protected]>
*/
/**
@joeytwiddle
joeytwiddle / async-await-forEach-alternatives.md
Last active April 24, 2025 05:32
Do not use forEach with async-await

Do not use forEach with async-await

TLDR: Use for...of instead of forEach() in asynchronous code.

For legacy browsers, use for...i or [].reduce()

To execute the promises in parallel, use Promise.all([].map(...))

The problem

@slikts
slikts / react-memo-children.md
Last active November 20, 2024 15:48
Why using the `children` prop makes `React.memo()` not work

nelabs.dev

Why using the children prop makes React.memo() not work

I've recently ran into a pitfall of [React.memo()][memo] that seems generally overlooked; skimming over the top results in Google just finds it mentioned in passing in a [React issue][regit], but not in the [FAQ] or API [overview][react-api], and not in the articles that set out to explain React.memo() (at least the ones I looked at). The issue is specifically that nesting children defeats memoization, unless the children are just plain text. To give a simplified code example:

const Memoized = React.memo(({ children }) => (<div>{children}</div>));
// Won't ever re-render
<Memoized>bar</Memoized>
// Will re-render every time; the memoization does nothing
@gaearon
gaearon / Classes.js
Created May 27, 2020 17:38
Beneath Classes: Prototypes
class Spiderman {
lookOut() {
alert('My Spider-Sense is tingling.');
}
}
let miles = new Spiderman();
miles.lookOut();
@sindresorhus
sindresorhus / esm-package.md
Last active April 29, 2025 15:28
Pure ESM package

Pure ESM package

The package that linked you here is now pure ESM. It cannot be require()'d from CommonJS.

This means you have the following choices:

  1. Use ESM yourself. (preferred)
    Use import foo from 'foo' instead of const foo = require('foo') to import the package. You also need to put "type": "module" in your package.json and more. Follow the below guide.
  2. If the package is used in an async context, you could use await import(…) from CommonJS instead of require(…).
  3. Stay on the existing version of the package until you can move to ESM.

Создание разметки при помощи JS

Перед чтением

Перед чтением убедитесь, что вам знакомы следующие концепции:

  • [DOM]
  • [Functions]
  • [Classes]
  • [OOP]