mirror of https://github.com/rust-lang/rust
40 lines
680 B
Rust
40 lines
680 B
Rust
struct Point {
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x: isize,
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y: isize,
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}
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fn a() {
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let mut p = vec![1];
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// Create an immutable pointer into p's contents:
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let q: &isize = &p[0];
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p[0] = 5; //~ ERROR cannot borrow
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println!("{}", *q);
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}
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fn borrow<F>(_x: &[isize], _f: F) where F: FnOnce() {}
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fn b() {
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// here we alias the mutable vector into an imm slice and try to
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// modify the original:
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let mut p = vec![1];
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borrow(
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&p,
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|| p[0] = 5); //~ ERROR cannot borrow `p` as mutable
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}
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fn c() {
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// Legal because the scope of the borrow does not include the
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// modification:
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let mut p = vec![1];
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borrow(&p, ||{});
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p[0] = 5;
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}
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fn main() {
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}
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