Master ES6+ features including async/await, destructuring, spread operators, arrow functions, promises, modules, iterators, generators, and functional programming patterns for writing clean, efficient JavaScript code. Use when refactoring legacy code, implementing modern patterns, or optimizing JavaScript applications.
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What the file says
# Modern JavaScript Patterns
Comprehensive guide for mastering modern JavaScript (ES6+) features, functional programming patterns, and best practices for writing clean, maintainable, and performant code.
## When to Use This Skill
- Refactoring legacy JavaScript to modern syntax
- Implementing functional programming patterns
- Optimizing JavaScript performance
- Writing maintainable and readable code
- Working with asynchronous operations
- Building modern web applications
- Migrating from callbacks to Promises/async-await
- Implementing data transformation pipelines
## ES6+ Core Features
### 1. Arrow Functions
**Syntax and Use Cases:**
```javascript
// Traditional function
function add(a, b) {
return a + b;
}
// Arrow function
const add = (a, b) => a + b;
// Single parameter (parentheses optional)
const double = x => x * 2;
// No parameters
const getRandom = () => Math.random();
// Multiple statements (need curly braces)
const processUser = user => {
const normalized = user.name.toLowerCase();
return { ...user, name: normalized };
};
// Returning objects (wrap in parentheses)
const createUser = (name, age) => ({ name, age });
```
**Lexical 'this' Binding:**
…
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