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//@ check-fail
#![feature(rustc_attrs)]
trait Parser<'s> {
type Output;
fn call(&self, input: &'s str) -> (&'s str, Self::Output);
}
impl<'s, F, T> Parser<'s> for F
where F: Fn(&'s str) -> (&'s str, T) {
type Output = T;
fn call(&self, input: &'s str) -> (&'s str, T) {
self(input)
}
}
fn foo<F1, F2>(
f1: F1,
base: &'static str,
f2: F2
)
where
F1: for<'a> Parser<'a>,
F2: FnOnce(&<F1 as Parser>::Output) -> bool
{
let s: String = base.to_owned();
let str_ref = s.as_ref();
let (remaining, produced) = f1.call(str_ref);
assert!(f2(&produced));
assert_eq!(remaining.len(), 0);
}
struct Wrapper<'a>(&'a str);
fn main() {
fn bar<'a>(s: &'a str) -> (&'a str, &'a str) {
(&s[..1], &s[..])
}
fn baz<'a>(s: &'a str) -> (&'a str, Wrapper<'a>) {
(&s[..1], Wrapper(&s[..]))
}
foo(bar, "string", |s| s.len() == 5);
//~^ ERROR implementation of `FnOnce` is not general enough
//~| ERROR implementation of `FnOnce` is not general enough
foo(baz, "string", |s| s.0.len() == 5);
//~^ ERROR implementation of `FnOnce` is not general enough
//~| ERROR implementation of `FnOnce` is not general enough
}
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