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100 lines
1.4 KiB
Rust
100 lines
1.4 KiB
Rust
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#![feature(untagged_unions)]
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#![allow(dead_code)]
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use std::hash::{Hash, Hasher};
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#[derive(PartialEq, Hash)]
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struct Foo;
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impl PartialEq<u64> for Foo {
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fn eq(&self, _: &u64) -> bool { true }
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}
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#[derive(Hash)]
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struct Bar;
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impl PartialEq for Bar {
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fn eq(&self, _: &Bar) -> bool { true }
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}
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#[derive(Hash)]
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struct Baz;
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impl PartialEq<Baz> for Baz {
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fn eq(&self, _: &Baz) -> bool { true }
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}
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#[derive(PartialEq)]
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struct Bah;
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impl Hash for Bah {
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fn hash<H: Hasher>(&self, _: &mut H) {}
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}
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#[derive(Copy)]
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struct Qux;
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impl Clone for Qux {
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fn clone(&self) -> Self { Qux }
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}
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// looks like unions don't support deriving Clone for now
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#[derive(Copy)]
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union Union {
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a: u8,
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}
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impl Clone for Union {
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fn clone(&self) -> Self {
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Union {
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a: 42,
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}
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}
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}
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// See #666
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#[derive(Copy)]
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struct Lt<'a> {
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a: &'a u8,
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}
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impl<'a> Clone for Lt<'a> {
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fn clone(&self) -> Self { unimplemented!() }
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}
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// Ok, `Clone` cannot be derived because of the big array
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#[derive(Copy)]
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struct BigArray {
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a: [u8; 65],
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}
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impl Clone for BigArray {
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fn clone(&self) -> Self { unimplemented!() }
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}
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// Ok, function pointers are not always Clone
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#[derive(Copy)]
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struct FnPtr {
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a: fn() -> !,
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}
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impl Clone for FnPtr {
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fn clone(&self) -> Self { unimplemented!() }
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}
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// Ok, generics
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#[derive(Copy)]
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struct Generic<T> {
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a: T,
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}
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impl<T> Clone for Generic<T> {
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fn clone(&self) -> Self { unimplemented!() }
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}
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fn main() {}
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