1 // Copyright 2016 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 #![feature(question_mark, question_mark_carrier)]
13 // Test that type inference fails where there are multiple possible return types
14 // for the `?` operator.
16 fn f(x: &i32) -> Result<i32, ()> {
20 fn g() -> Result<Vec<i32>, ()> {
22 l.iter().map(f).collect()? //~ ERROR type annotations required: cannot resolve