mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-23 15:23:46 +00:00
56 lines
1.2 KiB
Rust
56 lines
1.2 KiB
Rust
// run-pass
|
|
#![allow(unused_must_use)]
|
|
#![allow(dead_code)]
|
|
// pretty-expanded FIXME #23616
|
|
|
|
trait Matcher {
|
|
fn next_match(&mut self) -> Option<(usize, usize)>;
|
|
}
|
|
|
|
struct CharPredMatcher<'a, 'b> {
|
|
str: &'a str,
|
|
pred: Box<dyn FnMut(char) -> bool + 'b>,
|
|
}
|
|
|
|
impl<'a, 'b> Matcher for CharPredMatcher<'a, 'b> {
|
|
fn next_match(&mut self) -> Option<(usize, usize)> {
|
|
None
|
|
}
|
|
}
|
|
|
|
trait IntoMatcher<'a, T> {
|
|
fn into_matcher(self, _: &'a str) -> T;
|
|
}
|
|
|
|
impl<'a, 'b, F> IntoMatcher<'a, CharPredMatcher<'a, 'b>> for F where F: FnMut(char) -> bool + 'b {
|
|
fn into_matcher(self, s: &'a str) -> CharPredMatcher<'a, 'b> {
|
|
CharPredMatcher {
|
|
str: s,
|
|
pred: Box::new(self),
|
|
}
|
|
}
|
|
}
|
|
|
|
struct MatchIndices<M> {
|
|
matcher: M
|
|
}
|
|
|
|
impl<M: Matcher> Iterator for MatchIndices<M> {
|
|
type Item = (usize, usize);
|
|
|
|
fn next(&mut self) -> Option<(usize, usize)> {
|
|
self.matcher.next_match()
|
|
}
|
|
}
|
|
|
|
fn match_indices<'a, M, T: IntoMatcher<'a, M>>(s: &'a str, from: T) -> MatchIndices<M> {
|
|
let string_matcher = from.into_matcher(s);
|
|
MatchIndices { matcher: string_matcher }
|
|
}
|
|
|
|
fn main() {
|
|
let s = "abcbdef";
|
|
match_indices(s, |c: char| c == 'b')
|
|
.collect::<Vec<_>>();
|
|
}
|