resiter/
while_ok.rs

1//
2// This Source Code Form is subject to the terms of the Mozilla Public
3// License, v. 2.0. If a copy of the MPL was not distributed with this
4// file, You can obtain one at http://mozilla.org/MPL/2.0/.
5//
6
7/// Extension trait for `Iterator<Item = Result<O, E>>` to iter until an error is encountered.
8pub trait WhileOk<O, E> {
9    /// Perform an on each `Ok` value. Stop on first `Err`
10    ///
11    /// ```
12    /// use resiter::while_ok::WhileOk;
13    /// use std::str::FromStr;
14    ///
15    /// let mut s = 0;
16    ///
17    /// let res = ["1", "2", "3", "4", "5"]
18    ///     .iter()
19    ///     .map(|txt| usize::from_str(txt))
20    ///     .while_ok(|i| s += i);
21    ///
22    /// assert_eq!(s, 15);
23    /// assert!(res.is_ok());
24    /// ```
25    /// When every value is `Ok` stop the iteration at the end of the iterator:
26    /// ```
27    /// use resiter::while_ok::WhileOk;
28    /// use std::str::FromStr;
29    ///
30    /// let mut s = 0;
31    ///
32    /// let res = ["1", "2", "a", "4", "5"]
33    ///     .iter()
34    ///     .map(|txt| usize::from_str(txt))
35    ///     .while_ok(|i| s += i);
36    ///
37    /// assert_eq!(s, 3);
38    /// assert!(res.is_err());
39    /// ```
40    fn while_ok<F>(self, _: F) -> Result<(), E>
41    where
42        F: FnMut(O);
43}
44
45impl<I, O, E> WhileOk<O, E> for I
46where
47    I: Iterator<Item = Result<O, E>>,
48{
49    #[inline]
50    fn while_ok<F>(self, mut f: F) -> Result<(), E>
51    where
52        F: FnMut(O),
53    {
54        for res in self {
55            f(res?);
56        }
57        Ok(())
58    }
59}
resiter/while_ok.rs

resiter/
while_ok.rs
