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//@ run-pass
// See Issues #20055 and #21695.
// We are checking here that the temporaries `Box<[i8, k]>`, for `k`
// in 1, 2, 3, 4, that are induced by the match expression are
// properly handled, in that only *one* will be initialized by
// whichever arm is run, and subsequently dropped at the end of the
// statement surrounding the `match`.
trait Boo {
fn dummy(&self) { } //~ WARN method `dummy` is never used
}
impl Boo for [i8; 1] { }
impl Boo for [i8; 2] { }
impl Boo for [i8; 3] { }
impl Boo for [i8; 4] { }
pub fn foo(box_1: fn () -> Box<[i8; 1]>,
box_2: fn () -> Box<[i8; 2]>,
box_3: fn () -> Box<[i8; 3]>,
box_4: fn () -> Box<[i8; 4]>,
) {
println!("Hello World 1");
let _: Box<dyn Boo> = match 3 {
1 => box_1(),
2 => box_2(),
3 => box_3(),
_ => box_4(),
};
println!("Hello World 2");
}
pub fn main() {
fn box_1() -> Box<[i8; 1]> { Box::new( [1; 1] ) }
fn box_2() -> Box<[i8; 2]> { Box::new( [1; 2] ) }
fn box_3() -> Box<[i8; 3]> { Box::new( [1; 3] ) }
fn box_4() -> Box<[i8; 4]> { Box::new( [1; 4] ) }
foo(box_1, box_2, box_3, box_4);
}
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