rx_rust/operators/creating/
never.rs

1use crate::utils::types::MaybeSend;
2use crate::{
3    observable::{Observable, Subscription},
4    observer::Observer,
5};
6use std::convert::Infallible;
7
8/// Creates an Observable that emits no items and never terminates.
9/// See <https://reactivex.io/documentation/operators/empty-never-throw.html>
10///
11/// # Examples
12/// ```rust
13/// use rx_rust::{
14///     observable::ObservableExt,
15///     operators::creating::never::Never,
16/// };
17/// use std::convert::Infallible;
18///
19/// let _subscription = Never.subscribe_with_callback(
20///     |_: Infallible| -> () { panic!("`Never` should not emit values") },
21///     |_| panic!("`Never` should not terminate"),
22/// );
23/// ```
24#[derive(Debug, Clone)]
25pub struct Never;
26
27impl<'or> Observable<'or, Infallible, Infallible> for Never {
28    type D = ();
29
30    fn subscribe(
31        self,
32        _: impl Observer<Infallible, Infallible> + MaybeSend + 'or,
33    ) -> Subscription<Self::D> {
34        Subscription::default()
35    }
36}
rx_rust/operators/creating/never.rs

rx_rust/operators/creating/
never.rs
