45 lines
1.0 KiB
Rust
45 lines
1.0 KiB
Rust
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type point = { x: int, y: int };
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impl foo for point {
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pure fn +(z: int) -> int { self.x + self.y + z }
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fn *(z: int) -> int { self.x * self.y * z }
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}
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fn a() {
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let mut p = {x: 3, y: 4};
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// ok (we can loan out rcvr)
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p + 3;
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p * 3;
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}
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fn b() {
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let mut p = {x: 3, y: 4};
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// Here I create an outstanding loan and check that we get conflicts:
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&mut p; //! NOTE prior loan as mutable granted here
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//!^ NOTE prior loan as mutable granted here
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p + 3; //! ERROR loan of mutable local variable as immutable conflicts with prior loan
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p * 3; //! ERROR loan of mutable local variable as immutable conflicts with prior loan
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}
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fn c() {
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// Here the receiver is in aliased memory and hence we cannot
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// consider it immutable:
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let q = @mut {x: 3, y: 4};
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// ...this is ok for pure fns
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*q + 3;
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// ...but not impure fns
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*q * 3; //! ERROR illegal borrow unless pure: creating immutable alias to aliasable, mutable memory
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//!^ NOTE impure due to access to impure function
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}
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fn main() {
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}
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