make function take multiple variables from an array passed in as parameter

Question

How to make function take multiple variables from an array passed in as parameter?

Edited

For example:

Achieve this:

const inputObj = [
 ['Anna', 10, 'Monday'],
 ['Anna', 15, 'Wednesday'],
 ['Beatrice', 8, 'Monday'],
 ['Beatrice', 11, 'Wednesday'],
 ['Anna', 4, 'Wednesday'],
 ['Beatrice', 5, 'Monday'],
 ['Beatrice', 16, 'Monday']
]
// expected output:
const outputObj = [ 
[ 'Anna', 10, 'Monday' ],
  [ 'Anna', 19, 'Wednesday' ],
  [ 'Beatrice', 29, 'Monday' ],
  [ 'Beatrice', 11, 'Wednesday' ] 
]

const arr = [0, 2]

const someFunction = (obj, v, a) => {
    const result = obj.reduce((acc, cur) => {
        const key = `${cur[a[0]]}|${cur[a[1]]}`
        if(!acc[key]) acc[key] = cur
        else acc[key][1] += cur[v]
        return acc
      }, {})
    return Object.values(result)
}


console.log(someFunction(inputObj, 1, arr))

with this:

const arr = [0, 2, 3, ...] // basically the array could contain any number of items.

const someFunction = (obj, v, objParams) => {
      const result = obj.reduce((acc, cur) => {
      const key = ??? 
      ...
      }, {})
}

So that the function can be reused and it accepts custom-sized arrays, check if the column numbers in the array are the same, then adds the sum of the column that is passed in as v?

How to declare the variables from the objParams to achieve the same result as the code above does?

Also how to add v in the middle of cur?

const key = objParams.join('|') seems to be what you want

Jaromanda X
– Jaromanda X

2018-05-30 00:23:46 +00:00
Commented May 30, 2018 at 0:23 — Jaromanda X
– Jaromanda X, Commented May 30, 2018 at 0:23

tehp · Accepted Answer · 2018-05-30 00:31:17Z

1

Assuming objParams is an array of unknown size (strings in this example):

const objParams = ["c1", "c2", "c3"];
const key = objParams.join(']}|${cur[');
const built = '${cur[' + key + ']';

Built is:

${cur[c1]}|${cur[c2]}|${cur[c3]

answered May 30, 2018 at 0:31

tehp

6,5752 gold badges29 silver badges34 bronze badges

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

1 Comment

Viet Over a year ago

Actually, this doesn't work. It returns the right key but the key doesn't work. Try console.log(key), it returns the key itself as a string, not the values of the keys.

Lex · Accepted Answer · 2018-05-30 00:36:00Z

1

With ES6 you can use the spread operator in the argument definition.

More reading about spread operator on MDN

function sum(...args) {
  return args.reduce((result, value) => result + value, 0)
}

const numbers = [1, 2, 3];

console.log('sum', sum(2, 2));
console.log('sum', sum(...numbers));
console.log('sum', sum(1, 2, 1, ...numbers));

// get single args before accumulating the rest
function sum2(foo, bar, ...args) {
  return args.reduce((result, value) => result + value, 0)
}

console.log('sum2', sum2(2, 2));
console.log('sum2', sum2(...numbers));
console.log('sum2', sum2(1, 2, 1, ...numbers));

answered May 30, 2018 at 0:36

Lex

5,0844 gold badges48 silver badges70 bronze badges

Collectives™ on Stack Overflow

make function take multiple variables from an array passed in as parameter

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related