It is time to see the best things about the new Typescript 4.0. Recently, Microsoft announced a new version that will enhance the productivity and efficiency of the language. Of course, all of us now know about the Typescript (that’s why you are here, right?). For the people who want a quick overview, here it is. Typescript is a language that is built over JavaScript. Here, you will get many new things that you are waiting for.

Let’s get into our main topic that is about the new things in TypeScript 4.0

You will get the following things

  • Better Editor…

List of methods:

  1. Pluck
  2. ApplySpec
  3. Cond
  4. PropEq
  5. Pipe
  6. FromPairs
  7. PathOr

Pluck

Using all the time. Go throw the array and take the value which we put as the key

const getAges = R.pluck(‘age’);getAges([{name: ‘fred’, age: 29}, {name: ‘wilma’, age: 27}]); //=> [29, 27]

ApplySpec

The gold key when we would like to format or translate our values of the object

const getTranslated = R.applySpec({  header: i18n.translate,  content: i18n.translate});getTranslated(article); //=> {header: ‘Translated header’, content: ‘Translated content’}

Cond

The devilish replacement for all the mad “switch” and all the awful if / else cases.

const fn = R.cond([  [R.equals(0), R.always(‘water …

React is an incredibly versatile JavaScript framework that allows developers to create intuitive interfaces for web applications. A React developer earns $57 per hour on average plus they are widely sought after in the market. React was introduced by Facebook and it is a favorite of many web developers in the world.

In this article, we will be going over the top 10 interview questions related to React Hooks, which were introduced in ver 16.8 to address some issues within the framework.

Q1. What Are React Hooks?

These are in-built functions that allow developers to use state and lifecycle methods within components in React. Each…


User Interface has become an essential part of modern development. Several technologies are used together to create attractive and high-performing user interfaces. Creating a simple user interface, with few screens is not a big deal, but as the application grows, the user interface becomes more and more complicated.

The Storybook is a tool that is very helpful while working user interface components. It is basically a development environment in which a developer can create components in an organized manner in isolation.

In this article, we will discuss when to use the storybook.

1. When you need to develop components in isolation

Suppose you are working on a component and…


В этой статье расскажу о том когда и как использовать React.memo и хук useCallback. После этой статьи поймете в каких случаях используют useCallback. Узнаете как работает между собой React.Memo и useCallback.

Кратко о React.memo и useCallback

React.Memo — компонент высшего порядка. Похож на React.PureComponent, но предназначен для функциональных компонентов.

Вторым аргументом React.Memo есть возможность передать функцию которая будет принимать решение ре-рендерить компонент на основе предыдущих и нынешних props

Компонент высшего порядка — функция принимает дочерний компонент и параметры, и затем создаёт контейнер поверх дочернего компонента.

React.PureComponent — схож с React.Component, но единственная разница в методе shouldComponentUpdate.

В PureComponent сравнивает новые значения с предыдущими и возвращает…


In this article, I’ll talk about when and how to use React.memo and the useCallback hook. After this article, you will understand when to use useCallback. Learn how React.Memo and useCallback work together.

Briefly about React.memo and useCallback

React.Memo is a higher-order component. Similar to React.PureComponent, but intended for functional components.

The second argument of React.Memo is the ability to pass a function that will decide to re-render the component based on previous and current props

Higher-order component — the function takes a child component and parameters, and then creates a container on top of the child component.

React.PureComponent — similar to React.Component, but the…


Multithreading is what made great computing speeds possible. Today, it is a compulsory feature in all operating systems and programming languages. While even the old languages like C++ added built-in thread support in the somewhat latest updates, JavaScript remained stubborn.

But multithreading was needed in browsers nonetheless, so the concept of event loop is used to perform asynchronous functions in JavaScript. Event loop monitors message queue and the execution stack to make sure callback functions are executed as soon as the execution stack is empty. The callback functions are further divided into micro-tasks and macro-tasks.

We will look at the…

Michael Pautov

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