mirror of https://github.com/rust-lang/rust
41 lines
753 B
Rust
41 lines
753 B
Rust
struct Point { x: isize, y: isize }
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trait Methods {
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fn impurem(&self);
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fn blockm<F>(&self, f: F) where F: FnOnce();
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}
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impl Methods for Point {
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fn impurem(&self) {
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}
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fn blockm<F>(&self, f: F) where F: FnOnce() { f() }
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}
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fn a() {
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let mut p = Point {x: 3, y: 4};
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// Here: it's ok to call even though receiver is mutable, because we
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// can loan it out.
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p.impurem();
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// But in this case we do not honor the loan:
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p.blockm(|| { //~ ERROR cannot borrow `p` as mutable
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p.x = 10;
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})
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}
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fn b() {
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let mut p = Point {x: 3, y: 4};
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// Here I create an outstanding loan and check that we get conflicts:
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let l = &mut p;
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p.impurem(); //~ ERROR cannot borrow
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l.x += 1;
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}
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fn main() {
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}
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