mapToGroups()

The mapToGroups method iterates through the collection and passes each value to the given callback:

const collection = collect([
  { id: 1, name: "A" },
  { id: 2, name: "B" },
  { id: 3, name: "C" },
  { id: 4, name: "B" }
]);

const groups = collection.mapToGroups(function(item, key) {
  return [item.name, item.id];
});

//=> {
//=>   A: [1],
//=>   B: [2, 4],
//=>   C: [3],
//=> }

View source on GitHub