Why I need to wrap this in brackets?

1

Hi, this is one line from my code:

    tasksArray = tasksArray.map((taskItem, index) => {id: index + 1, task: taskItem.task})

It is not working when it’s constructed like this, however then I’m adding the brackets around the object that is created for every array item (I mean like that ({id: index + 1, task: taskItem.task})) it’s working excelent, why is that happening? I dont understand this syntax code, why shouldn’t we use curly brackets like we do with every function () => {}???

2

Braces are used in arrow functions if you want it to be multi-line (just like in a regular function):

(x, y) => {
  const z = x + y;
  return z;
}

What’s happening in your arrow function is that the braces are interpreted as the beginning and end of a function body, not as an object literal. Kind of like:

function(taskItem, index) {
  id: index + 1,
  task: taskItem.task
}

Now that isn’t really what you want.

If you intend for an arrow function to return an object, you’ll need to wrap the braces with a set of parentheses. Basically JS will treat the code in the parentheses as a single value, in this case as a single object.

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