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Start your free trialSamuel Kleos
Front End Web Development Techdegree Student 13,679 PointsIs this approach okay? #flatten #reduce #map
Hey, I reduced it first because I wanted to access a flattened array of title objects.
// flatten favouriteBooks objects and map over objects to extract title strings.
const titles = users
.reduce((arr, user) => [...arr, ...user.favoriteBooks], [])
.map(book => book.title)
console.log(titles);
// DATA SOURCE
const users = [
{
name: 'Samir',
age: 27,
favoriteBooks:[
{title: 'The Iliad'},
{title: 'The Brothers Karamazov'}
]
},
{
name: 'Angela',
age: 33,
favoriteBooks:[
{title: 'Tenth of December'},
{title: 'Cloud Atlas'},
{title: 'One Hundred Years of Solitude'}
]
},
{
name: 'Beatrice',
age: 42,
favoriteBooks:[
{title: 'Candide'}
]
}
];
1 Answer
Steven Parker
231,272 PointsSure, it doesn't matter which order you use the reduce and map, you still get the same result.
But … you must define users before you can reference it to create titles. That order is important.