Struct RefType

pub struct RefType { /* private fields */ }

Opaque references to data in the Wasm heap or to host data.

Subtyping and Equality

RefType does not implement Eq, because reference types have a subtyping relationship, and so 99.99% of the time you actually want to check whether one type matches (i.e. is a subtype of) another type. You can use the RefType::matches and Ref::matches_ty methods to perform these types of checks. If, however, you are in that 0.01% scenario where you need to check precise equality between types, you can use the RefType::eq method.

Implementations

impl RefType

pub const EXTERNREF: Self

The externref type, aka (ref null extern).

pub const NULLEXTERNREF: Self

The nullexternref type, aka (ref null noextern).

pub const FUNCREF: Self

The funcref type, aka (ref null func).

pub const NULLFUNCREF: Self

The nullfuncref type, aka (ref null nofunc).

pub const ANYREF: Self

The anyref type, aka (ref null any).

pub const I31REF: Self

The i31ref type, aka (ref null i31).

pub const ARRAYREF: Self

The arrayref type, aka (ref null array).

pub const STRUCTREF: Self

The structref type, aka (ref null struct).

pub const NULLREF: Self

The nullref type, aka (ref null none).

pub fn new(is_nullable: bool, heap_type: HeapType) -> RefType

Construct a new reference type.

pub fn is_nullable(&self) -> bool

Can this type of reference be null?

pub fn heap_type(&self) -> &HeapType

The heap type that this is a reference to.

pub fn matches(&self, other: &RefType) -> bool

Does this reference type match the other?

That is, is this reference type a subtype of the other?

Panics

Panics if either type is associated with a different engine from the other.

pub fn eq(a: &RefType, b: &RefType) -> bool

Is reference type a precisely equal to reference type b?

Returns false even if a is a subtype of b or vice versa, if they are not exactly the same reference type.

Panics

Panics if either type is associated with a different engine.

Trait Implementations

impl Clone for RefType

fn clone(&self) -> RefType

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for RefType

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

Formats the value using the given formatter.

impl Display for RefType

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

Formats the value using the given formatter.

impl From<RefType> for ValType

fn from(r: RefType) -> Self

Converts to this type from the input type.

impl Hash for RefType

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.