Struct ThrownException

pub struct ThrownException;

Available on crate features gc and runtime only.

An error type that represents that a pending WebAssembly exception is set on the associated Store.

When used as an error type and returned from a Wasm-to-host call, or host-to-Wasm call, it indicates that the caller should either continue propagating the error upward, or take and handle the exception using [crate::Store::take_exception] (or a helper such as [crate::Store::catch].

Wasmtime uses an error type without payload, and stores the exception itself on the store, to maintain proper GC rooting; otherwise, it is difficult to get exception propagation up the stack right in the presence of nested handle scopes. A pending exception on the store is safely rooted as long as it is stored there.

Trait Implementations

impl Debug for ThrownException

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

Formats the value using the given formatter.

impl Display for ThrownException

Error requires Display.

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

Formats the value using the given formatter.

impl Error for ThrownException

We need to implement Error for ThrownException so it can be boxed up into an anyhow::Error.

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.