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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

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
229,708 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.