42 lines
1.4 KiB
Rust
42 lines
1.4 KiB
Rust
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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fn a<'a, 'b, 'c>(x: &mut &'a isize, y: &mut &'b isize, z: &mut &'c isize) where 'b: 'a + 'c {
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// Note: this is legal because of the `'b:'a` declaration.
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*x = *y;
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*z = *y;
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}
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fn b<'a, 'b, 'c>(x: &mut &'a isize, y: &mut &'b isize, z: &mut &'c isize) {
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// Illegal now because there is no `'b:'a` declaration.
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*x = *y; //~ ERROR cannot infer
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*z = *y; //~ ERROR cannot infer
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}
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fn c<'a,'b, 'c>(x: &mut &'a isize, y: &mut &'b isize, z: &mut &'c isize) {
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// Here we try to call `foo` but do not know that `'a` and `'b` are
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// related as required.
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a(x, y, z); //~ ERROR cannot infer
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}
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fn d() {
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// 'a and 'b are early bound in the function `a` because they appear
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// inconstraints:
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let _: fn(&mut &isize, &mut &isize, &mut &isize) = a; //~ ERROR mismatched types
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}
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fn e() {
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// 'a and 'b are late bound in the function `b` because there are
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// no constraints:
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let _: fn(&mut &isize, &mut &isize, &mut &isize) = b;
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}
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fn main() { }
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