Python: How to Reverse a String

• Translate URLs/slugs (e.g., /about-us → /fr/a-propos)
• Maintain SEO with hreflang for each language
• Improve UX by aligning URLs with user language
• Ensure route accessibility via browser language or manual switching

• How to structure language-specific routes
• How to integrate URL translation with react-router-dom
• How to switch routes with language changes
• Bonus: how to integrate with react-i18next

React example:

const today = new Intl.DateTimeFormat(i18n.language).format(new Date());

If you don’t have a project yet, initialize a new one:

npx create-react-app react-i18n-demo
cd react-i18n-demo

We’ll build two apps:

/app-shell         (React)
  ├── webpack.config.js
  ├── src/
      └── bootstrap.js

/analytics-app     (Vue)
  ├── webpack.config.js
  ├── src/
      └── main.js

   npm install zustand

   import create from 'zustand';

   const useStore = create((set) => ({
     count: 0,
     increase: () => set((state) => ({ count: state.count + 1 })),
     decrease: () => set((state) => ({ count: state.count - 1 })),
   }));

React re-renders components when there's a change in state or props. While this ensures the UI stays in sync with data, it can also lead to redundant renders, especially in large component trees. Identifying and mitigating these unnecessary re-renders is key to optimizing performance.([GeeksforGeeks][2])

React.memo is a higher-order component that prevents functional components from re-rendering if their props haven't changed. It performs a shallow comparison of props and reuses the previous render result when possible.([JavaScript in Plain English][3])

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console.log(5 == "5"); // true (type coercion)
console.log(5 === "5"); // false (no type coercion)
console.log(10 > 7); // true
console.log(4 <= 4); // true

Logical operators combine multiple conditions or values.

• Converts the operand to a number and negates it.
• Example:

     let x = "5";
     let num = -x; // -5 (number)

• Arrow Functions (ES6):

  const multiply = (a, b) => a * b;
  console.log(multiply(4, 7)); // 28

• Syntax: Append n to the end of an integer.
• Example:

  let bigNumber = 123456789012345678901234567890n;
  console.log(bigNumber);

     let age = 25;
     age = 26; // Allowed
     console.log(age); // 26

• Used for variables whose value should not change.
• Example:

• What happens?
• The console.log() function outputs text to the console.
• "Hello, World!" is a string (text) enclosed in double quotes.

• In a browser:
• Open the console (Ctrl+Shift+J or Cmd+Option+J) and type the code.
• In Node.js:
• Save the code in a file (e.g., hello.js) and run it using:

     Running JavaScript with Node.js!

• Example of reading a file:

     console.log("Hello, World!");

• Use the console like a calculator:

To write and test JavaScript effectively, you need a code editor. While there are many options available, Visual Studio Code (VS Code) is one of the most popular choices due to its versatility and rich feature set.

• Visit the official VS Code website.
• Choose the version for your operating system (Windows, macOS, or Linux).

• JavaScript enables features like dropdown menus, modal windows, sliders, and real-time updates.
• Examples: Search suggestions, form validations, chat applications.

• Using AJAX or Fetch API, JavaScript retrieves and updates data without reloading the page.
• Example: Infinite scrolling on social media feeds.

• Created by Brendan Eich in just 10 days while working at Netscape.
• Originally named Mocha, then renamed LiveScript, and finally JavaScript to ride the popularity wave of Java.

• JavaScript was standardized under the name ECMAScript by ECMA International.
• The first edition of ECMAScript (ES1) laid the foundation for modern JavaScript.

Create a new folder for your project, and within it, create the following files:

- manifest.json
- background.js
- content.js
- popup.html
- popup.js

Managing state in large-scale React applications can become complex. Redux Toolkit (RTK) simplifies Redux development by:

• Eliminating Boilerplate: Simplifies writing reducers, actions, and middleware.
• Built-in DevTools Support: Includes powerful debugging tools like time-travel debugging.
• Better Performance: Optimized for immutability and efficient state updates.
• Built-in Async Handling: Simplifies API calls and async state management with createAsyncThunk.