Psst: have a look at the JavaScript Console for output. 💁

.sum(), .every(), .find(), .findIndex()


      
const people = [ { name: 'Wes', year: 1988 }, { name: 'Kait', year: 1986 }, { name: 'Irv', year: 1970 }, { name: 'Lux', year: 2015 } ];
// is at least one person 19? const isAdult = people.some(person => ((new Date()).getFullYear()) - person.year >= 19); console.log({isAdult}); // is everyone 19? const allAdults = people.every(person => ((new Date()).getFullYear()) - person.year >= 19); console.log({allAdults});

const comments = [ { text: 'Love this!', id: 523423 }, { text: 'Super good', id: 823423 }, { text: 'You are the best', id: 2039842 }, { text: 'Ramen is my fav food ever', id: 123523 }, { text: 'Nice Nice Nice!', id: 542328 } ];
// find the comment with the ID of 823423 const comment = comments.find(comment => comment.id === 823423); console.log(comment); // Find the comment with this ID // delete the comment with the ID of 823423 const index = comments.findIndex(comment => comment.id === 823423); console.log(index); console.table(comments); const newComments = [ ...comments.slice(0, index), ...comments.slice(index + 1) ]; console.table(newComments);