Struct Layout

pub struct Layout {
    pub size: Option<u64>,
    pub align: Option<u64>,
    pub discriminant_offset: Option<u64>,
    pub uninhabited: bool,
    pub variant_layouts: Vector<VariantId, VariantLayout>,
}

Simplified type layout information.

Does not include information about niches. If the type does not have fully known layout (e.g. it is ?Sized) some of the layout parts are not available.

Fields

size: Option<u64>

The size of the type in bytes.

align: Option<u64>

The alignment, in bytes.

discriminant_offset: Option<u64>

The discriminant’s offset, if any. Only relevant for types with multiple variants.

uninhabited: bool

Whether the type is uninhabited, i.e. has any valid value at all. Note that uninhabited types can have arbitrary layouts: (u32, !) has space for the u32 and enum E2 { A, B(!), C(i32, !) } may have space for a discriminant.

variant_layouts: Vector<VariantId, VariantLayout>

Map from VariantId to the corresponding field layouts. Structs are modeled as having exactly one variant, unions as having no variant.

Trait Implementations

impl AstVisitable for Layout

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 Layout

fn clone(&self) -> Layout

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Layout

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

Formats the value using the given formatter.

impl Default for Layout

fn default() -> Layout

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Layout

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 Layout

where V: Visitor + Visit<'s, Vector<VariantId, VariantLayout>>,

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 Layout

where V: Visitor + VisitMut<'s, Vector<VariantId, VariantLayout>>,

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 Layout

fn eq(&self, other: &Layout) -> 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 Layout

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 Layout

impl StructuralPartialEq for Layout