Struct VariantLayout

pub struct VariantLayout {
    pub field_offsets: Vector<FieldId, u64>,
    pub uninhabited: bool,
    pub tag: Option<ScalarValue>,
}

Simplified layout of a single variant.

Maps fields to their offset within the layout.

Fields

field_offsets: Vector<FieldId, u64>

The offset of each field.

uninhabited: bool

Whether the variant is uninhabited, i.e. has any valid possible value. Note that uninhabited types can have arbitrary layouts.

tag: Option<ScalarValue>

The memory representation of the discriminant corresponding to this variant. It must be of the same type as the corresponding DiscriminantLayout::tag_ty.

If it’s None, then this variant is either:

• the untagged variant (cf. TagEncoding::Niche::untagged_variant) of a niched enum;
• the single variant of a struct;
• uninhabited.

Trait Implementations

impl AstVisitable for VariantLayout

fn drive<V: VisitAst>(&self, v: &mut V) -> ControlFlow<V::Break>

Recursively visit this type with the provided visitor. This calls the visitor’s visit_$any method if it exists, otherwise visit_inner.

fn drive_mut<V: VisitAstMut>(&mut self, v: &mut V) -> ControlFlow<V::Break>

Recursively visit this type with the provided visitor. This calls the visitor’s visit_$any method if it exists, otherwise visit_inner.

fn name(&self) -> &'static str

The name of the type, used for debug logging.

fn dyn_visit<T: AstVisitable>(&self, f: impl FnMut(&T))

Visit all occurrences of that type inside self, in pre-order traversal.

fn dyn_visit_mut<T: AstVisitable>(&mut self, f: impl FnMut(&mut T))

Visit all occurrences of that type inside self, in pre-order traversal.

impl Clone for VariantLayout

fn clone(&self) -> VariantLayout

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for VariantLayout

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for VariantLayout

fn default() -> VariantLayout

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for VariantLayout

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<'s, V> Drive<'s, V> for VariantLayout

where V: Visitor,

fn drive_inner(&'s self, visitor: &mut V) -> ControlFlow<V::Break>

Call v.visit() on the immediate contents of self.

impl<'s, V> DriveMut<'s, V> for VariantLayout

where V: Visitor,

fn drive_inner_mut(&'s mut self, visitor: &mut V) -> ControlFlow<V::Break>

Call v.visit() on the immediate contents of self.

impl PartialEq for VariantLayout

fn eq(&self, other: &VariantLayout) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for VariantLayout

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for VariantLayout

impl StructuralPartialEq for VariantLayout