pub enum Variants<'a> {
    Single {
        index: VariantIdx,
    },
    Multiple {
        tag: Scalar,
        tag_encoding: TagEncoding,
        tag_field: usize,
        variants: IndexVec<VariantIdx, Layout<'a>>,
    },
}

Variants

Single

Fields

index: VariantIdx

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

Multiple

Fields

tag: Scalar
tag_encoding: TagEncoding
tag_field: usize
variants: IndexVec<VariantIdx, Layout<'a>>

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

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 ==. Read more

This method tests for !=.

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 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: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.

Size: 112 bytes

Size for each variant:

  • Single: 4 bytes
  • Multiple: 108 bytes