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// Test that we reliably check the value of the associated type.
#![crate_type = "lib"]
#![no_implicit_prelude]
use std::option::Option::{self, None, Some};
use std::vec::Vec;
trait Iterator {
type Item;
fn next(&mut self) -> Option<Self::Item>;
}
fn is_iterator_of<A, I: Iterator<Item=A>>(_: &I) {}
struct Adapter<I> {
iter: I,
found_none: bool,
}
impl<T, I> Iterator for Adapter<I> where I: Iterator<Item=Option<T>> {
type Item = T;
fn next(&mut self) -> Option<T> {
loop {}
}
}
fn test_adapter<T, I: Iterator<Item=Option<T>>>(it: I) {
is_iterator_of::<Option<T>, _>(&it); // Sanity check
let adapter = Adapter { iter: it, found_none: false };
is_iterator_of::<T, _>(&adapter); // OK
is_iterator_of::<Option<T>, _>(&adapter); //~ ERROR type mismatch
}
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