mirror of https://github.com/rust-lang/rust
33 lines
813 B
Rust
33 lines
813 B
Rust
// This test is illustrating the difference between how failing to derive
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// `PartialEq` is handled compared to failing to implement it at all.
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// See also RFC 1445
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#[derive(PartialEq, Eq)]
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struct Structural(u32);
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struct NoPartialEq(u32);
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struct NoDerive(u32);
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// This impl makes NoDerive irreflexive.
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impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
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impl Eq for NoDerive { }
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const NO_DERIVE_NONE: Option<NoDerive> = None;
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const NO_PARTIAL_EQ_NONE: Option<NoPartialEq> = None;
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fn main() {
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match None {
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NO_DERIVE_NONE => println!("NO_DERIVE_NONE"),
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_ => panic!("whoops"),
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}
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match None {
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NO_PARTIAL_EQ_NONE => println!("NO_PARTIAL_EQ_NONE"),
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//~^ ERROR must be annotated with `#[derive(PartialEq)]`
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_ => panic!("whoops"),
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}
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}
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