# concat

Concatenates all the observable sequences. This takes in either an array or variable arguments to concatenate.

## Arguments

1. `args` _(`arguments` | `Array`)_: An array or arguments of Observable sequences.

## Returns

_(`Observable`)_: An observable sequence that contains the elements of each given sequence, in sequential order.

## Example

```javascript
/* Using Promises and Observable sequences */
var source1 = Rx.Observable.return(42);
var source2 = RSVP.Promise.resolve(56);

var source = Rx.Observable.concat(source1, source2);

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

// => Next: 42
// => Next: 56
// => Completed
```
