spread operator javascript
let a = { a: 0, b: 1 };
let b = { b: 2, c: 3 };
let c = { ...a, ...b };
console.log(c);
output -> {a: 0, b: 2, c: 3}let arr1 = ['A', 'B', 'C'];
let arr2 = ['X', 'Y', 'Z'];
let result = [...arr1, ...arr2];
console.log(result); // ['A', 'B', 'C', 'X', 'Y', 'Z']
// spread elements of the array instead of taking the array as a wholeobj = {first_name : "Marty",
lovers: ["Jennifer Parker","Baines McFly"]
};
let objClone = { ...obj }; // pass all key:value pairs from an object
console.log(objClone)
// { first_name: "Marty", lovers: ["Jennifer Parker", "Baines McFly"] }const parts = ['shoulders', 'knees'];
const lyrics = ['head', ...parts, 'and', 'toes'];
// ["head", "shoulders", "knees", "and", "toes"]
function sum(x, y, z) {
return x + y + z;
}
const numbers = [1, 2, 3];
console.log(sum(...numbers));
// expected output: 6
// This will add each item in number arrray in sum method.
console.log(sum.apply(null, numbers));
// expected output: 6[a, b, ...objIteravel] = [1, 2, 3, 4, 5];