// Copyright 2015 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 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. pub type Session = i32; pub struct StreamParser<'a, T> { _tokens: T, _session: &'a mut Session, } impl<'a, T> StreamParser<'a, T> { pub fn thing(&mut self) -> bool { true } } pub fn parse_stream, U, F>( _session: &mut Session, _tokens: T, _f: F) -> U where F: Fn(&mut StreamParser) -> U { panic!(); } pub fn thing(session: &mut Session) { let mut stream = vec![1, 2, 3].into_iter(); let _b = parse_stream(session, stream.by_ref(), // replacing the above with the following fixes it //&mut stream, |p| p.thing()); } fn main() {}