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JavaScript

MING-HSIEN CHEN
MING-HSIEN CHEN
11,852 Points
Posted by MING-HSIEN CHEN
MING-HSIEN CHEN
11,852 Points

Arrow function

Hey everybody, In the video, we see an arrow function like this below: const flatMovies = movies.reduce((arr, innerMovies)=>[...arr, ...innerMovie], []);

my question is: what is the reason why we don' t need a curly braces after the fat arrow like below: const flatMovies = movies.reduce((arr, innerMovies)=>{ [...arr, ...innerMovie], []) };

Thank you.

1 Answer

Stuart Wright
Stuart Wright
41,120 Points
Stuart Wright
Stuart Wright
41,120 Points

If a JavaScript arrow function body contains only a single statement, the braces are not required. If a single statement comes after the arrow, the JavaScript interpreter knows that that is what needs to be returned, so there's no need for the braces. You only need to add braces for multi-line functions.