rust/src/test/compile-fail/object-lifetime-default-ambiguous.rs
2015-02-16 11:58:47 -05:00

62 lines
1.5 KiB
Rust

// 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 <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.
// Test that if a struct declares multiple region bounds for a given
// type parameter, an explicit lifetime bound is required on object
// lifetimes within.
#![allow(dead_code)]
trait Test {
fn foo(&self) { }
}
struct Ref0<T:?Sized> {
r: *mut T
}
struct Ref1<'a,T:'a+?Sized> {
r: &'a T
}
struct Ref2<'a,'b:'a,T:'a+'b+?Sized> {
r: &'a &'b T
}
fn a<'a,'b>(t: Ref2<'a,'b,Test>) {
//~^ ERROR lifetime bound for this object type cannot be deduced from context
}
fn b(t: Ref2<Test>) {
//~^ ERROR lifetime bound for this object type cannot be deduced from context
}
fn c(t: Ref2<&Test>) {
// In this case, the &'a overrides.
}
fn d(t: Ref2<Ref1<Test>>) {
// In this case, the lifetime parameter from the Ref1 overrides.
}
fn e(t: Ref2<Ref0<Test>>) {
//~^ ERROR lifetime bound for this object type cannot be deduced from context
//
// In this case, Ref2 is ambiguous, and Ref0 inherits the
// ambiguity.
}
fn f(t: &Ref2<Test>) {
//~^ ERROR lifetime bound for this object type cannot be deduced from context
}
fn main() {
}