# Concat¶

• Official ReactiveX documentation: Concat
Observable.concat_all()

Concatenates an observable sequence of observable sequences.

Returns an observable sequence that contains the elements of each observed inner sequence, in sequential order.

classmethod Observable.concat(*args)

Concatenates all the observable sequences.

1 - res = Observable.concat(xs, ys, zs) 2 - res = Observable.concat([xs, ys, zs])

Returns an observable sequence that contains the elements of each given sequence, in sequential order.