Struct externref::Resource

#[repr(C)]
pub struct Resource<T> { /* private fields */ }

Host resource exposed to WASM.

Internally, a resource is just an index into the externrefs table; thus, it is completely valid to store Resources on heap (in a Vec, thread-local storage, etc.). The type param can be used for type safety.

Implementations

impl<T> Resource<T>

pub fn upcast(self) -> Resource<()>

Upcasts this resource to a generic resource.

pub fn upcast_ref(&self) -> &Resource<()>

Upcasts a reference to this resource to a generic resource reference.

impl Resource<()>

pub unsafe fn downcast_unchecked<T>(self) -> Resource<T>

Downcasts this generic resource to a specific type.

Safety

No checks are performed that the resource actually encapsulates what is meant by Resource<T>. It is up to the caller to check this beforehand (e.g., by calling a WASM import taking &Resource<()> and returning an app-specific resource kind).

Trait Implementations

impl<T: Debug> Debug for Resource<T>

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

Formats the value using the given formatter.

impl<T> Drop for Resource<T>

Drops the externref associated with this resource.

fn drop(&mut self)

Executes the destructor for this type.