6.short_circuiting.js

//SHORT CIRCUITING
//In certain conditions the operator will return the first value and not look at the second value
//Short-circuiting means JavaScript stops evaluating an expression as soon as it knows the final result.

const data = [
  {
    id: 1,
    title: "The Lord of the Rings",
    publicationDate: "1954-07-29",
    author: "J. R. R. Tolkien",
    genres: [
      "fantasy",
      "high-fantasy",
      "adventure",
      "fiction",
      "novels",
      "literature",
    ],
    hasMovieAdaptation: true,
    pages: 1216,
    translations: {
      spanish: "El señor de los anillos",
      chinese: "魔戒",
      french: "Le Seigneur des anneaux",
    },
    reviews: {
      goodreads: {
        rating: 4.52,
        ratingsCount: 630994,
        reviewsCount: 13417,
      },
      librarything: {
        rating: 4.53,
        ratingsCount: 47166,
        reviewsCount: 452,
      },
    },
  },
  {
    id: 2,
    title: "The Cyberiad",
    publicationDate: "1965-01-01",
    author: "Stanislaw Lem",
    genres: [
      "science fiction",
      "humor",
      "speculative fiction",
      "short stories",
      "fantasy",
    ],
    hasMovieAdaptation: false,
    pages: 295,
    translations: {},
    reviews: {
      goodreads: {
        rating: 4.16,
        ratingsCount: 11663,
        reviewsCount: 812,
      },
      librarything: {
        rating: 4.13,
        ratingsCount: 2434,
        reviewsCount: 0,
      },
    },
  },
  {
    id: 3,
    title: "Dune",
    publicationDate: "1965-01-01",
    author: "Frank Herbert",
    genres: ["science fiction", "novel", "adventure"],
    hasMovieAdaptation: true,
    pages: 658,
    translations: {
      spanish: "",
    },
    reviews: {
      goodreads: {
        rating: 4.25,
        ratingsCount: 1142893,
        reviewsCount: 49701,
      },
    },
  },
  {
    id: 4,
    title: "Harry Potter and the Philosopher's Stone",
    publicationDate: "1997-06-26",
    author: "J. K. Rowling",
    genres: ["fantasy", "adventure"],
    hasMovieAdaptation: true,
    pages: 223,
    translations: {
      spanish: "Harry Potter y la piedra filosofal",
      korean: "해리 포터와 마법사의 돌",
      bengali: "হ্যারি পটার এন্ড দ্য ফিলোসফার্স স্টোন",
      portuguese: "Harry Potter e a Pedra Filosofal",
    },
    reviews: {
      goodreads: {
        rating: 4.47,
        ratingsCount: 8910059,
        reviewsCount: 140625,
      },
      librarything: {
        rating: 4.29,
        ratingsCount: 120941,
        reviewsCount: 1960,
      },
    },
  },
  {
    id: 5,
    title: "A Game of Thrones",
    publicationDate: "1996-08-01",
    author: "George R. R. Martin",
    genres: ["fantasy", "high-fantasy", "novel", "fantasy fiction"],
    hasMovieAdaptation: true,
    pages: 835,
    translations: {
      korean: "왕좌의 게임",
      polish: "Gra o tron",
      portuguese: "A Guerra dos Tronos",
      spanish: "Juego de tronos",
    },
    reviews: {
      goodreads: {
        rating: 4.44,
        ratingsCount: 2295233,
        reviewsCount: 59058,
      },
      librarything: {
        rating: 4.36,
        ratingsCount: 38358,
        reviewsCount: 1095,
      },
    },
  },
];

function getBooks(id){
    return data.find((d) => d.id ==id);
}

const bookThree = getBooks(3)
const pages = bookThree.pages

const condition = pages > 1000 ? "over 1000 pages" : "less than 1000 pages";

// The && operator = short circuits when the first operand, when the firt value is false; Returns the first falsy value
console.log(true && "some string");
console.log(false && "some string");

//////falsy values = 0, '', undefined
console.log("jonas" && "some string")
console.log(0 && "some string")


// The || operator = short circuits when the first operand, when the first value is true; Returns the first truthy value
console.log(bookThree.translations.spanish);

const spanishTranslation = bookThree.translations.spanish || "NOT TRANSLATION";
spanishTranslation


//Nullish coalescing — Returns the first non-null/undefined value
console.log(null ?? "Default"); // "Default"
console.log(undefined ?? "Fallback"); // "Fallback"
console.log(0 ?? 100); // 0 (not nullish)