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pub trait WhileOk<O, E>
{
fn while_ok<F>(self, F) -> Result<(), E>
where F: FnMut(O) -> ();
}
impl<I, O, E> WhileOk<O, E> for I
where I: Iterator<Item = Result<O, E>>,
{
fn while_ok<F>(self, mut f: F) -> Result<(), E>
where F: FnMut(O) -> ()
{
for res in self {
f(res?);
}
Ok(())
}
}
#[test]
fn test_while_ok_ok() {
use std::str::FromStr;
let mut s = 0;
let res = ["1", "2", "3", "4", "5"]
.into_iter()
.map(|txt| usize::from_str(txt))
.while_ok(|i| s += i);
assert_eq!(s, 15);
assert!(res.is_ok());
}
#[test]
fn test_while_ok_err() {
use std::str::FromStr;
let mut s = 0;
let res = ["1", "2", "a", "4", "5"]
.into_iter()
.map(|txt| usize::from_str(txt))
.while_ok(|i| s += i);
assert_eq!(s, 3);
assert!(res.is_err());
}