Clean up StructuralEq
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@ -156,18 +156,18 @@ pub trait StructuralPartialEq {
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/// Required trait for constants used in pattern matches.
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///
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/// Any type that derives `Eq` automatically implements this trait, *regardless*
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/// of whether its type-parameters implement `Eq`.
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/// of whether its type parameters implement `Eq`.
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///
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/// This is a hack to workaround a limitation in our type-system.
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/// This is a hack to work around a limitation in our type system.
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///
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/// Background:
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/// # Background
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///
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/// We want to require that types of consts used in pattern matches
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/// have the attribute `#[derive(PartialEq, Eq)]`.
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///
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/// In a more ideal world, we could check that requirement by just checking that
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/// the given type implements both (1.) the `StructuralPartialEq` trait *and*
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/// (2.) the `Eq` trait. However, you can have ADTs that *do* `derive(PartialEq, Eq)`,
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/// the given type implements both the `StructuralPartialEq` trait *and*
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/// the `Eq` trait. However, you can have ADTs that *do* `derive(PartialEq, Eq)`,
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/// and be a case that we want the compiler to accept, and yet the constant's
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/// type fails to implement `Eq`.
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///
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@ -176,8 +176,11 @@ pub trait StructuralPartialEq {
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/// ```rust
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/// #[derive(PartialEq, Eq)]
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/// struct Wrap<X>(X);
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///
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/// fn higher_order(_: &()) { }
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///
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/// const CFN: Wrap<fn(&())> = Wrap(higher_order);
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///
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/// fn main() {
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/// match CFN {
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/// CFN => {}
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