How to extract array of arrays values and push in same array in ES6?

Issue

I have this array of array

a1 = [['one', 'two', ['three', 'four']], ['five', 'six', ['seven', 'eight']]];

how to get this 'three' and 'four', 'seven' and 'eight' out of child array and push it in parent array as string like below

a2 = [['one', 'two', 'three, four'], ['five', 'six', 'seven, eight']];

like this. can I solve it with ES6?

Note: with space between 'three' 'four' and 'seven' 'eight' as shown in a2.

Solution

Sounds like you want to join the inner arrays, yeah?

let a1 = [['one', 'two', ['three', 'four']], ['five', 'six', ['seven', 'eight']]];
let merged = a1.map((values) => {
  return values.map((value) => {
    return Array.isArray(value) ? value.join(', ') : value;
  });
});
console.log(merged)

Answered By - nickf