44 lines
1 KiB
Rust
44 lines
1 KiB
Rust
type point = { x: int, y: int };
|
|
|
|
impl foo for point {
|
|
pure fn +(z: int) -> int { self.x + self.y + z }
|
|
fn *(z: int) -> int { self.x * self.y * z }
|
|
}
|
|
|
|
fn a() {
|
|
let mut p = {x: 3, y: 4};
|
|
|
|
// ok (we can loan out rcvr)
|
|
p + 3;
|
|
p * 3;
|
|
}
|
|
|
|
fn b() {
|
|
let mut p = {x: 3, y: 4};
|
|
|
|
// Here I create an outstanding loan and check that we get conflicts:
|
|
|
|
&mut p; //! NOTE prior loan as mutable granted here
|
|
//!^ NOTE prior loan as mutable granted here
|
|
|
|
p + 3; //! ERROR loan of mutable local variable as immutable conflicts with prior loan
|
|
p * 3; //! ERROR loan of mutable local variable as immutable conflicts with prior loan
|
|
}
|
|
|
|
fn c() {
|
|
// Here the receiver is in aliased memory and hence we cannot
|
|
// consider it immutable:
|
|
let q = @mut {x: 3, y: 4};
|
|
|
|
// ...this is ok for pure fns
|
|
*q + 3;
|
|
|
|
|
|
// ...but not impure fns
|
|
*q * 3; //! ERROR illegal borrow unless pure: creating immutable alias to aliasable, mutable memory
|
|
//!^ NOTE impure due to access to impure function
|
|
}
|
|
|
|
fn main() {
|
|
}
|
|
|