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Begana ChoiCourses Plus Student 13,123 Points
what is the difference between those two codes?
const books = users .map(user => user.favoriteBooks.map(book=> book.title)) .reduce((books, title) => books.concat(title), );
const books = users .map(user => user.favoriteBooks) .map(book=> book.title) .reduce((books, title) => books.concat(title), );
in my head both codes are logical but when I run the code, the second doesn't work.
Steven Parker211,091 Points
In the first example, the 2nd "map" is applied to a single "favoriteBooks" array.
But in the 2nd example, the 2nd "map" is being applied to an array of "favoriteBooks" arrays, which would not have a "title" attribute.