472685f0d7
- Introduced gamification service spec detailing responsibilities, API surface, XP calculation, levels, streaks, badges, milestone cards, and heatmap data. - Added generation service spec outlining the process for generating micro learning content, including API endpoints, AI call configuration, prompt strategies, and error handling. - Created R42 chat service spec covering chatbot interactions, retrieval pipeline, prompt construction, response generation, and stateless design principles.
73 lines
2.2 KiB
Markdown
73 lines
2.2 KiB
Markdown
# Introduction to TypeScript
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TypeScript is a strongly typed programming language that builds on JavaScript, giving you better tooling at any scale.
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## Type System
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TypeScript adds optional static typing and class-based object-oriented programming to the language. Types provide a way to describe the shape of an object, providing better documentation, and allowing TypeScript to validate that your code is working correctly.
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### Basic Types
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TypeScript supports several basic types including `string`, `number`, `boolean`, `array`, and `tuple`. These types allow you to add type annotations to your variables and function parameters.
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## Interfaces
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Interfaces define the shape of an object in TypeScript. They are a powerful way to define contracts within your code as well as contracts with code outside of your project.
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```typescript
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interface User {
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name: string;
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age: number;
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email?: string;
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}
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```
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An interface can define optional properties using the `?` operator. This is useful when some properties may or may not be present.
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## Classes
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TypeScript supports full class-based object-oriented programming with inheritance, interfaces, and access modifiers. Classes provide a clean and reusable way to create objects.
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```typescript
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class Animal {
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private name: string;
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constructor(name: string) {
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this.name = name;
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}
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public move(distance: number = 0): void {
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console.log(`${this.name} moved ${distance}m.`);
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}
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}
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```
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Access modifiers (`public`, `private`, `protected`) control visibility of class members.
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## Generics
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Generics provide a way to make components work with any data type and not restrict to one data type. They allow users to consume these components and use their own types.
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```typescript
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function identity<T>(arg: T): T {
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return arg;
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}
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```
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Generics are particularly useful for building reusable data structures and functions that work across multiple types.
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## Enums
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Enumerations allow you to define a set of named constants. TypeScript provides both numeric and string-based enums.
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```typescript
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enum Direction {
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Up = "UP",
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Down = "DOWN",
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Left = "LEFT",
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Right = "RIGHT",
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}
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```
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String enums are more readable than numeric enums because they provide meaningful string values at runtime.
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