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#![feature(default_field_values)]
#[derive(Debug)]
pub struct S;
#[derive(Debug, Default)]
pub struct Foo {
pub bar: S = S,
pub baz: i32 = 42 + 3,
}
#[derive(Debug, Default)]
pub struct Bar {
pub bar: S, //~ ERROR the trait bound `S: Default` is not satisfied
pub baz: i32 = 42 + 3,
}
#[derive(Default)]
pub struct Qux<const C: i32> {
bar: S = Self::S,
baz: i32 = foo(),
bat: i32 = <Qux<{ C }> as T>::K,
bay: i32 = C,
}
pub struct Rak(i32 = 42); //~ ERROR default fields are not supported in tuple structs
impl<const C: i32> Qux<C> {
const S: S = S;
}
trait T {
const K: i32;
}
impl<const C: i32> T for Qux<C> {
const K: i32 = 2;
}
const fn foo() -> i32 {
42
}
#[derive(Debug, Default)]
enum E {
#[default]
Variant {} //~ ERROR the `#[default]` attribute may only be used on unit enum variants
}
fn main () {
let _ = Foo { .. }; // ok
let _ = Foo::default(); // ok
let _ = Bar { .. }; //~ ERROR missing field
let _ = Bar { baz: 0, .. }; //~ ERROR missing field
let _ = Bar::default(); // silenced
let _ = Bar { bar: S, .. }; // ok
let _ = Qux::<4> { .. };
let _ = Rak(..); //~ ERROR E0308
//~^ you might have meant to use `..` to skip providing
let _ = Rak(0, ..); //~ ERROR E0061
//~^ you might have meant to use `..` to skip providing
let _ = Rak(.., 0); //~ ERROR E0061
//~^ you might have meant to use `..` to skip providing
let _ = Rak { .. }; // ok
}
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