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//@ run-pass
#[derive(PartialEq, Debug)]
pub struct Partial<T> { x: T, y: T }
#[derive(PartialEq, Debug)]
struct S { val: isize }
impl S { fn new(v: isize) -> S { S { val: v } } }
impl Drop for S { fn drop(&mut self) { } }
pub fn f<T, F>((b1, b2): (T, T), mut f: F) -> Partial<T> where F: FnMut(T) -> T {
let p = Partial { x: b1, y: b2 };
// Move of `p` is legal even though we are also moving `p.y`; the
// `..p` moves all fields *except* `p.y` in this context.
Partial { y: f(p.y), ..p }
}
pub fn main() {
let p = f((S::new(3), S::new(4)), |S { val: z }| S::new(z+1));
assert_eq!(p, Partial { x: S::new(3), y: S::new(5) });
}
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