ES6 Create an array of array that contains pairs

Question

I have the following data model. I'm trying to array reduce and create pairs of objects from it. Also, if there is an odd number i'll add that to the last pair.

Given data:

const pairs = [ {name: bob, value: foo}, {name: jane, value: foo}, {name: mary, value: foo}, {name: elizabeth, value: foo}, {name: colin, value: foo}]

Would like to get the following output:

const pairs = [ 

    [{name: bob, value: foo}, {name: jane, value: foo}],
    [{name: mary, value: foo}, {name: elizabeth, value: foo}, {name: colin, value: foo}]
]

What i've tried so far is:

const result = pairs.reduce((acc, curr, i, array) => {
    const acc = acc.length % 3 === 0 ? acc.slice(acc.length -1, acc.length) : acc.push(curr);
    return acc
}, []);

Is there a simple way to do this with Array.reduce()?

No, don't use reduce for this. There are so many much simpler alternatives. — Bergi
– Bergi, Commented Nov 5, 2018 at 17:50
There's a good example in there that uses reduce. Thanks Bergi — chrisl-921fb74d
– chrisl-921fb74d, Commented Nov 5, 2018 at 18:33

Przemek · Accepted Answer · 2018-11-06 17:29:46Z

1

const pairs = [
  {name: 'bob',       value: 'foo'},
  {name: 'jane',      value: 'foo'},
  {name: 'mary',      value: 'foo'},
  {name: 'elizabeth', value: 'foo'},
  {name: 'colin',     value: 'foo'}
];

const flooredHalf = parseInt(pairs.length / 2);
const result = new Array(flooredHalf);
for (let i = 0; i <= flooredHalf; i += 2) {
  result[i / 2] = pairs.slice(i, (i + 3 === pairs.length ? i + 3 : i + 2));
}

/* DEMO */
console.log(JSON.stringify(result));

answered Nov 6, 2018 at 17:29

Przemek

4,0042 gold badges28 silver badges34 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

ES6 Create an array of array that contains pairs

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related