| @@ -1118,6 +1118,11 @@ impl fmt::Debug for Discriminant { |
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/// |
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/// [Reference]: ../../reference/items/enumerations.html#custom-discriminant-values-for-fieldless-enumerations |
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/// |
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+/// The value of a [`Discriminant`] is independent of any *lifetimes* in `T`. As such, reading |
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+/// or writing a `Discriminant<Foo<'a>>` as a `Discriminant<Foo<'b>>` (whether via [`transmute`] or |
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+/// otherwise) is always sound. Note that this is **not** true for other kinds of generic |
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+/// parameters; `Discriminant<Foo>` and `Discriminant<Foo>` might be incompatible. |
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+/// |
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/// # Examples |
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/// |
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/// This can be used to compare enums that carry data, while disregarding |