mirror of https://github.com/rust-lang/rust
31 lines
878 B
Rust
31 lines
878 B
Rust
fn a<'a, 'b:'a>(x: &mut &'a isize, y: &mut &'b isize) {
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// Note: this is legal because of the `'b:'a` declaration.
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*x = *y;
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}
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fn b<'a, 'b>(x: &mut &'a isize, y: &mut &'b isize) {
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// Illegal now because there is no `'b:'a` declaration.
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*x = *y; //~ ERROR: lifetime may not live long enough
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}
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fn c<'a,'b>(x: &mut &'a isize, y: &mut &'b 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); //~ ERROR: lifetime may not live long enough
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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) = a;
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//~^ ERROR mismatched types [E0308]
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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) = b;
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}
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fn main() { }
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