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trait S: Sized {
fn tpb(&mut self, _s: Self) {}
}
impl S for i32 {}
fn two_phase1() {
let mut x = 3;
x.tpb(x);
}
fn two_phase2() {
let mut v = vec![];
v.push(v.len());
}
fn two_phase3(b: bool) {
let mut x = &mut vec![];
let mut y = vec![];
x.push((
{
if b {
x = &mut y;
}
22
},
x.len(),
));
}
#[allow(unreachable_code)]
fn two_phase_raw() {
let x: &mut Vec<i32> = &mut vec![];
x.push({
// Unfortunately this does not trigger the problem of creating a
// raw ponter from a pointer that had a two-phase borrow derived from
// it because of the implicit &mut reborrow.
let raw = x as *mut _;
unsafe {
*raw = vec![1];
}
return;
});
}
fn two_phase_overlapping1() {
let mut x = vec![];
let p = &x;
x.push(p.len());
}
fn two_phase_overlapping2() {
use std::ops::AddAssign;
let mut x = 1;
let l = &x;
x.add_assign(x + *l);
}
fn with_interior_mutability() {
use std::cell::Cell;
trait Thing: Sized {
fn do_the_thing(&mut self, _s: i32) {}
}
impl<T> Thing for Cell<T> {}
let mut x = Cell::new(1);
let l = &x;
x.do_the_thing({
x.set(3);
l.set(4);
x.get() + l.get()
});
}
fn main() {
two_phase1();
two_phase2();
two_phase3(false);
two_phase3(true);
two_phase_raw();
with_interior_mutability();
two_phase_overlapping1();
two_phase_overlapping2();
}
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