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