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// Copyright 2014 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.
// Check that explicit region bounds are allowed on the various
// nominal types (but not on other types) and that they are type
// checked.
struct Inv<'a> { // invariant w/r/t 'a
x: &'a mut &'a isize
}
pub trait Foo<'a, 't> {
fn no_bound<'b>(self, b: Inv<'b>);
fn has_bound<'b:'a>(self, b: Inv<'b>);
fn wrong_bound1<'b,'c,'d:'a+'b>(self, b: Inv<'b>, c: Inv<'c>, d: Inv<'d>);
fn okay_bound<'b,'c,'d:'a+'b+'c>(self, b: Inv<'b>, c: Inv<'c>, d: Inv<'d>);
fn another_bound<'x: 'a>(self, x: Inv<'x>);
}
impl<'a, 't> Foo<'a, 't> for &'a isize {
fn no_bound<'b:'a>(self, b: Inv<'b>) {
//~^ ERROR lifetime parameters or bounds on method `no_bound` do not match
}
fn has_bound<'b>(self, b: Inv<'b>) {
//~^ ERROR lifetime parameters or bounds on method `has_bound` do not match
}
fn wrong_bound1<'b,'c,'d:'a+'c>(self, b: Inv<'b>, c: Inv<'c>, d: Inv<'d>) {
//~^ ERROR method `wrong_bound1` has an incompatible type for trait
//
// Note: This is a terrible error message. It is caused
// because, in the trait, 'b is early bound, and in the impl,
// 'c is early bound, so -- after substitution -- the
// lifetimes themselves look isomorphic. We fail because the
// lifetimes that appear in the types are in the wrong
// order. This should really be fixed by keeping more
// information about the lifetime declarations in the trait so
// that we can compare better to the impl, even in cross-crate
// cases.
}
fn okay_bound<'b,'c,'e:'b+'c>(self, b: Inv<'b>, c: Inv<'c>, e: Inv<'e>) {
}
fn another_bound<'x: 't>(self, x: Inv<'x>) {}
}
fn main() { }
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