30-seconds-of-code/snippets/chunkify.md

title, type, tags, author, cover, dateModified

title	type	tags	author	cover	dateModified
Chunk iterable	snippet	function generator array	chalarangelo	cave-view	2021-03-16T22:50:40+02:00

Chunks an iterable into smaller arrays of a specified size.

• Use a for...of loop over the given iterable, using Array.prototype.push() to add each new value to the current chunk.
• Use Array.prototype.length to check if the current chunk is of the desired size and yield the value if it is.
• Finally, use Array.prototype.length to check the final chunk and yield it if it's non-empty.

const chunkify = function* (itr, size) {
  let chunk = [];
  for (const v of itr) {
    chunk.push(v);
    if (chunk.length === size) {
      yield chunk;
      chunk = [];
    }
  }
  if (chunk.length) yield chunk;
};

const x = new Set([1, 2, 1, 3, 4, 1, 2, 5]);
[...chunkify(x, 2)]; // [[1, 2], [3, 4], [5]]