Group array elements
JavaScript, Array · Oct 22, 2020

Creates an array of elements, grouped based on their position in the original arrays.
- Use
Math.max()
,Function.prototype.apply()
to get the longest array in the arguments. - Create an array with that length as return value and use
Array.from()
with a mapping function to create an array of grouped elements. - If lengths of the argument arrays vary,
undefined
is used where no value could be found.
const zip = (...arrays) => { const maxLength = Math.max(...arrays.map(x => x.length)); return Array.from({ length: maxLength }).map((_, i) => { return Array.from({ length: arrays.length }, (_, k) => arrays[k][i]); }); }; zip(['a', 'b'], [1, 2], [true, false]); // [['a', 1, true], ['b', 2, false]] zip(['a'], [1, 2], [true, false]); // [['a', 1, true], [undefined, 2, false]]