return object with the same key and value from array

Question

[1,2].reduce((accum,val) => ({val}) ,{})

I expect above reduce function will return {1:1, 2:2} but it didn't, what's wrong? isn't I've return an object?

Nina Scholz · Accepted Answer · 2018-09-28 06:35:03Z

5

You need to spread the accumulator (working with newer JS or with babeljs) and computed property names.

console.log([1, 2].reduce((accum, val) => ({ ...accum, [val]: val }), {}));

answered Sep 28, 2018 at 6:35

Nina Scholz

388k26 gold badges367 silver badges417 bronze badges

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

Comments

Aaron · Accepted Answer · 2018-09-28 06:34:31Z

0

[1,2].reduce((accum,val) => { accum[val] = val
return accum } ,{})

This will do the trick. You weren't referencing the starting object.

answered Sep 28, 2018 at 6:34

Aaron

1,3069 silver badges10 bronze badges

Eddie · Accepted Answer · 2018-09-28 06:34:46Z

0

One option is using Object.assign to add new property and values

var result = [1, 2].reduce((accum, val) => Object.assign(accum, {[val]: val}), {})
console.log(result);

answered Sep 28, 2018 at 6:34

Eddie

26.8k6 gold badges39 silver badges59 bronze badges

Ashish · Accepted Answer · 2018-09-28 06:37:10Z

0

Use can write like this: You need to spread accumulator value.

[1,2].reduce((accum,val) => ({...accum, [val]:val}) ,{})

answered Sep 28, 2018 at 6:37

Ashish

4,3701 gold badge19 silver badges46 bronze badges