rust/tests/ui/borrowck/borrowck-loan-rcvr.rs
2023-01-11 09:32:08 +00:00

41 lines
753 B
Rust

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