Namaste React

Parcel

• Creates a Dev Build
• Creates a Local Server
• Does HMR = Hot Module Replacement
• Uses File Watching Algorithm - Written in C++ to do HMR
• Every time we save a file it recreates the builds and shows how much time it took it is mostly in milliseconds or seconds.
• Because it is caching the code that is why it takes so less time to rebuild it.
• Caching - for Faster Builds (it caches in parcel-cache folder which is available in your folder structure on local machine).
• Image Optimization
• Minification
• Bundling
• Compressing
• Consistent Hashing (Read on Google)
• Code Splitting
• Differential Bundling - to support older browsers
• Diagnostics
• Error Handling
• Also gives us a way to host app on HTTPs
• Tree Shaking (algo) - remove unused code
• Different dev and prod builds

Two types of Export/Import

• Default Export/Import
  • Export: export default ComponentName/VariableName
  • Import: import ComponentName/VariableName from "path"
  • Used for exporting and importing only one thing from the file
• Named Export/Import
  • Export: export ComponentName/VariableName
  • Import: import {ComponentName/VariableName} from "path"
  • Used for exporting and importing multiple thing from the file

React Hooks

- They are normal JS utility Functions - (written by react developers)
- They have written this inside react library

• They are two very important hooks
  • useState() - used to generate super powerful variables in react
  • useEffect()