dd() : The dd() method will console.log the collection and exit the current process:
const collection = collect([1, 2, 3]).dd();
// Collection { items: [ 1, 2, 3 ] }
// (Exits node.js process)
diff() : The diff() method compares the collection against another collection or a plain array based on its values. This method will return the values in the original collection that are not present in the given collection:
const collection = collect([1, 2, 3, 4, 5]);
const diff = collection.diff([1, 2, 3, 9]);
diff.all();
// [4, 5]
