Arrays In Javascript

• Can convert an object to an array of pairs with Object.entries()
• Check if item is in array:

const sections = ['contact', 'shipping'];

function displayShipping(sections) {
    return sections.includes('shipping');
}

console.log(displayShipping(sections));

Spread Operator

• Remove item from array (not modifying the original array) with the spread operator:

function removeItem(items, removable) {
    const index = items.indexOf(removable);
    return [...items.slice(0, index), ...items.slice(index + 1)];
}

• Use a provided array in a function and use it, while keeping the function pure:

function addGift(cart) {
  if (cart.length > 2) {
    return [...cart, reward];
  }
  return cart;
}

• Instead of sorting an array and mutating it, sort a copy of the array:

Created from: Modern Javascript Course 202006070113

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uid: 202006091927 tags: #programming #javascript

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