mirror of https://github.com/rust-lang/rust
26 lines
424 B
Rust
26 lines
424 B
Rust
use std::ops::Deref;
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struct MyPtr<'a>(&'a mut usize);
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impl<'a> Deref for MyPtr<'a> {
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type Target = usize;
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fn deref<'b>(&'b self) -> &'b usize { self.0 }
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}
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trait Tr {
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fn poke(&self, s: &mut usize);
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}
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impl Tr for usize {
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fn poke(&self, s: &mut usize) {
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*s = 2;
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}
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}
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fn main() {
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let s = &mut 1;
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MyPtr(s).poke(s);
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//~^ ERROR cannot borrow `*s` as mutable more than once at a time
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}
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