Enum rustc_abi::Variants

source ·
pub enum Variants<V: Idx> {
    Single {
        index: V,
    },
    Multiple {
        tag: Scalar,
        tag_encoding: TagEncoding<V>,
        tag_field: usize,
        variants: IndexVec<V, LayoutS<V>>,
    },
}

Variants§

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Single

Fields

§index: V

Single enum variants, structs/tuples, unions, and all non-ADTs.

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Multiple

Fields

§tag: Scalar
§tag_encoding: TagEncoding<V>
§tag_field: usize
§variants: IndexVec<V, LayoutS<V>>

Enum-likes with more than one inhabited variant: each variant comes with a discriminant (usually the same as the variant index but the user can assign explicit discriminant values). That discriminant is encoded as a tag on the machine. The layout of each variant is a struct, and they all have space reserved for the tag. For enums, the tag is the sole field of the layout.

Trait Implementations§

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Feeds this value into the given Hasher. Read more
Feeds a slice of this type into the given Hasher. Read more
This method tests for self and other values to be equal, and is used by ==.
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.

Layout§

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.