mapSpread()
The mapSpread method iterates over the collection's items, passing each nested item value into the given callback. The callback is free to modify the item and return it, thus forming a new collection of modified items:
const collection = collect([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
const chunks = collection.chunk(2);
const sequence = chunks.mapSpread((even, odd) => even + odd);
sequence.all();
// [1, 5, 9, 13, 17]