𝗙𝗿𝗼𝗺 𝗭𝗲𝗿𝗼 𝘁𝗼 𝗛𝗲𝗿𝗼 𝗶𝗻 𝗧𝘆𝗽𝗲𝗦𝗰𝗿𝗶𝗽𝘁

TypeScript makes your JavaScript code safer. It helps you find bugs before you run your code. This guide covers the path from basic to advanced concepts.

TypeScript adds static typing to JavaScript. It turns your code into plain JavaScript for the browser.

Basic Types

  • number: integers or decimals
  • boolean: true or false
  • string: text
  • symbol: unique identifiers
  • bigint: large integers

Type Annotations You define types during variable creation: let name: string = "Alice"; let age: number = 30;

Arrays and Objects

  • Arrays: let fruits: string[] = ["apple", "banana"];
  • Objects: let user: { name: string; age: number } = { name: "Bob", age: 25 };

Functions You can specify what a function takes and what it returns. Use void if the function returns nothing. function greet(name: string): string { return "Hello, " + name; }

Advanced Structures

  • Type Aliases: Define a custom name for a type.
  • Interfaces: Define the shape of an object.
  • Enums: Create a set of named constants.
  • Tuples: Create an array with a fixed number of elements and specific types.

Complex Logic

  • Union Types: Allow a variable to hold more than one type.
  • Intersection Types: Combine multiple types into one.
  • Generics: Create reusable components that work with many types.
  • Utility Types: Use built-in tools like Partial or Pick to change types.

Best Practices

  • Use type for simple aliases and primitives.
  • Use interface for object shapes.
  • Avoid using any. It removes the safety of TypeScript.
  • Use unknown instead of any when you are unsure of the type.
  • Let the compiler infer types when the code is clear.

TypeScript helps you build large applications with confidence.

Source: https://dev.to/miasalazar/from-zero-to-hero-in-typescript-425j