• Returns a Boolean value indicating if certain condition is true or not.
• some只要部分符合就會回傳true
• every要全部符合才會回傳true
• 一樣都需要call back function return 值

const record = [
  {name: "math", score: 89},
  {name: "chinese", score: 72},
  {name: "english", score: 91},
  {name: "science", score: 88}
];

// 是否有小於80成績 some
let result1 = record.some(i => {
  return i.score < 80;
});

// 是否成績全小於80 every
let result2 = record.every(i => {
  return i.score < 80;
});

console.log(result1); // true
console.log(result2); // false