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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data and Additional Exploration

Begana Choi
PLUS
Begana Choi
Courses Plus Student 13,126 Points
Posted by Begana Choi
Begana Choi
Courses Plus Student 13,126 Points

why concat doesn't work with {}?

const flatMovies = movies.reduce((arr,movie)=> {arr.concat(movie)},[]);

why this code doesn't work but without {} is working?

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

In the full arrow function syntax, where you have a code body in braces, nothing is returned unless you include an explicit "return" statement.

But in the abbreviated syntax, where you have only a single expression and no braces, the result of the expression is automatically returned.