> For the complete documentation index, see [llms.txt](https://soufatn.gitbook.io/rxjs-book/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://soufatn.gitbook.io/rxjs-book/summary/observable/observable_methods/zip.md).

# zip

Merges the specified observable sequences or Promises into one observable sequence by using the selector function whenever all of the observable sequences have produced an element at a corresponding index. If the result selector function is omitted, a list with the elements of the observable sequences at corresponding indexes will be yielded.

## Arguments

1. `args` *(`Array`|`arguments`)*: Observable sources.
2. `[resultSelector]` *(Function)*: A function which takes the inputs at the specified index and combines them together.  If omitted, a list with the elements of the observable sequences at corresponding indexes will be yielded.

## Returns

*(`Observable`)*: An observable sequence containing the result of combining elements of the sources using the specified result selector function.

## Example

### Without a result selector

```javascript
var range = Rx.Observable.range(0, 5);

var source = Observable.zip(
  range,
  range.skip(1),
  range.skip(2)
);

var subscription = source.subscribe(
  function (x) {
    console.log('Next: %s', x);
  },
  function (err) {
    console.log('Error: %s', err);
  },
  function () {
    console.log('Completed');
  });

// => Next: 0,1,2
// => Next: 1,2,3
// => Next: 2,3,4
// => Completed
```

### Using arguments

### Using promises and Observables \*/