Operadores Spread & Rest
JavaScript Syntax Guide
Expandir e coletar valores com operador ...
Operadores Spread & Rest
Expandir e coletar valores com operador ...
// Spread operator with arrays
const numbers = [1, 2, 3];
const moreNumbers = [...numbers, 4, 5, 6];
console.log(moreNumbers); // [1, 2, 3, 4, 5, 6]
// Copying arrays
const original = [1, 2, 3];
const copy = [...original];
copy.push(4);
console.log(original, copy); // [1, 2, 3], [1, 2, 3, 4]
// Spread with objects
const person = { name: 'John', age: 25 };
const updatedPerson = { ...person, city: 'New York' };
console.log(updatedPerson); // { name: 'John', age: 25, city: 'New York' }
// Merging objects
const obj1 = { a: 1, b: 2 };
const obj2 = { b: 3, c: 4 };
const merged = { ...obj1, ...obj2 };
console.log(merged); // { a: 1, b: 3, c: 4 }
// Rest operator in function parameters
function sum(first, ...rest) {
return rest.reduce((acc, num) => acc + num, first);
}
console.log(sum(1, 2, 3, 4)); // 10
// Rest in array destructuring
const [first, second, ...remaining] = [1, 2, 3, 4, 5];
console.log(first, second, remaining); // 1, 2, [3, 4, 5]
// Rest in object destructuring
const { a, b, ...others } = { a: 1, b: 2, c: 3, d: 4 };
console.log(a, b, others); // 1, 2, { c: 3, d: 4 }
Explanation
Common Use Cases
- Manipulação de arrays
- Mesclagem de objetos
- Argumentos de função
- Atualizações imutáveis
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Master Operadores Spread & Rest in JavaScript
Understanding Operadores Spread & Rest is fundamental to writing clean and efficient JavaScript code. This comprehensive guide provides you with practical examples and detailed explanations to help you master this important concept.
Whether you're a beginner learning the basics or an experienced developer looking to refresh your knowledge, our examples cover real-world scenarios and best practices for using Operadores Spread & Rest effectively in your JavaScript projects.
Key Takeaways
- Manipulação de arrays
- Mesclagem de objetos
- Argumentos de função