rust/src/test/run-pass/issue-14919.rs
2017-07-08 01:56:27 +03:00

63 lines
1.6 KiB
Rust

// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// pretty-expanded FIXME #23616
trait Matcher {
fn next_match(&mut self) -> Option<(usize, usize)>;
}
struct CharPredMatcher<'a, 'b> {
str: &'a str,
pred: Box<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<_>>();
}