Declaring Objects on the fly with .map()

JavaScript
1

Tell us what’s happening:

Why is it the case that this works:

const ratings = watchList.map(el => ({title: el.Title, rating: el.imdbRating}));

but this doesn’t:

const ratings = watchList.map(el => {title: el.Title, rating: el.imdbRating});

In the one that doesn’t work we’re declaring an Object literal to be added to the array that map will return? What makes the parentheses wrapping an Object literal different?

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Challenge: Use the map Method to Extract Data from an Array

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2

Parentheses allows here for implicit return. Otherwise brackets will be considered as a opening and closing of function body, what would require a traditional return statement.

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