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