Destructuring array of objects in es6

Question

In es6, how can I simplify the following lines using destructuring?

const array0 = someArray[0].data;
const array1 = someArray[1].data;
const array2 = someArray[2].data;

Answer 1

Whether using destructuring would actually be a simplification is debatable but this is how it can be done:

const [
  { data: array0 },
  { data: array1 },
  { data: array2 }
] = someArray

Live Example:

const someArray = [
  { data: 1 },
  { data: 2 },
  { data: 3 }
];

const [
  { data: array0 },
  { data: array1 },
  { data: array2 }
] = someArray

console.log(array0, array1, array2);

What is happening is that you're first extracting each object from someArray then destructuring each object by extracting the data property and renaming it:

// these 2 destructuring steps
const [ obj1, obj2, obj3 ] = someArray // step 1
const { data: array0 } = obj1 // step 2
const { data: array1 } = obj2 // step 2
const { data: array2 } = obj3 // step 2

// written together give
const [
  { data: array0 },
  { data: array1 },
  { data: array2 }
] = someArray

Maybe combine destructuring with mapping for (potentially) more readable code:

const [array0, array1, array2] = someArray.map(item => item.data)

Live Example:

const someArray = [
  { data: 1 },
  { data: 2 },
  { data: 3 }
];

const [array0, array1, array2] = someArray.map(item => item.data)

console.log(array0, array1, array2);