Mimicking behavior of document.cookie created by nidev - https://repl.it/@nidev/Mimicking-behavior-of-documentcookie

index.js

/*
document.cookie 의 구현을 흉내내보자

var wordJar = new WordJar();
wordJar.cookie = "apple";
// console.log(wordJar.cookie) -> "apple"
wordJar.cookie = "banana";
// console.log(wordJar.cookie) -> "apple, banana"
wordJar.cookie = "kiwi";
// console.log(wordJar.cookie) -> "apple, banana, kiwi"
wordJar.cookie = "!banana";
// console.log(wordJar.cookie) -> "apple, kiwi"

*/

function WordJar() {
  // 실제 단어가 저장되는 자료구조
  var wordJar = [];
  // 외부에 노출시킬 프로퍼티를 만들 객체
  var jarInterface = {};

  Object.defineProperty(jarInterface, "cookie", {
    configurable: false,
    enumerable: false,
    get: function() {
      return wordJar.join(", ");
    },
    set: function(keyword) {
      if (!keyword || typeof(keyword) !== "string") {
        return undefined;
      }

      var command = "append";

      if (keyword[0] === "!") {
        command = "remove";
        keyword = keyword.substring(1);
      }

      switch (command) {
        case "append":
          wordJar.push(keyword);
          break;
        case "remove":
          if (wordJar.indexOf(keyword) > -1) {
            wordJar.splice(wordJar.indexOf(keyword), 1);
          }
          break;
        default:
          throw "Unimplemented command: " + command;
      }

      return wordJar.join(", ");
    }
  });

  return jarInterface;
}

main(); function main() {
  var wordJar = new WordJar();
  wordJar.cookie = "apple";
  console.log(wordJar.cookie);// -> "apple"
  wordJar.cookie = "banana";
  console.log(wordJar.cookie);// -> "apple, banana"
  wordJar.cookie = "kiwi";
  console.log(wordJar.cookie);// -> "apple, banana, kiwi"
  wordJar.cookie = "!banana";
  console.log(wordJar.cookie);// -> "apple, kiwi"
}