Trait Host

pub trait Host {
    type AdviceProvider: AdviceProvider;

    // Required methods
    fn advice_provider(&self) -> &Self::AdviceProvider;
    fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider;
    fn get_mast_forest(
        &self,
        node_digest: &RpoDigest,
    ) -> Option<Arc<MastForest>>;

    // Provided methods
    fn on_event(
        &mut self,
        _process: ProcessState<'_>,
        _event_id: u32,
        _err_ctx: &ErrorContext<'_, impl MastNodeExt>,
    ) -> Result<(), ExecutionError> { ... }
    fn on_debug(
        &mut self,
        _process: ProcessState<'_>,
        _options: &DebugOptions,
    ) -> Result<(), ExecutionError> { ... }
    fn on_trace(
        &mut self,
        _process: ProcessState<'_>,
        _trace_id: u32,
    ) -> Result<(), ExecutionError> { ... }
    fn on_assert_failed(&mut self, _process: ProcessState<'_>, _err_code: Felt) { ... }
}

Defines an interface by which the VM can interact with the host.

There are four main categories of interactions between the VM and the host:

1. accessing the advice provider,
2. getting a library’s MAST forest,
3. handling advice events (which internally mutates the advice provider), and
4. handling debug and trace events.

Required Associated Types

type AdviceProvider: AdviceProvider

Required Methods

fn advice_provider(&self) -> &Self::AdviceProvider

Returns a reference to the advice provider.

fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider

Returns a mutable reference to the advice provider.

fn get_mast_forest(&self, node_digest: &RpoDigest) -> Option<Arc<MastForest>>

Returns MAST forest corresponding to the specified digest, or None if the MAST forest for this digest could not be found in this Host.

Provided Methods

fn on_event( &mut self, _process: ProcessState<'_>, _event_id: u32, _err_ctx: &ErrorContext<'_, impl MastNodeExt>, ) -> Result<(), ExecutionError>

Handles the event emitted from the VM.

fn on_debug( &mut self, _process: ProcessState<'_>, _options: &DebugOptions, ) -> Result<(), ExecutionError>

Handles the debug request from the VM.

fn on_trace( &mut self, _process: ProcessState<'_>, _trace_id: u32, ) -> Result<(), ExecutionError>

Handles the trace emitted from the VM.

fn on_assert_failed(&mut self, _process: ProcessState<'_>, _err_code: Felt)

Handles the failure of the assertion instruction.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl<H> Host for &mut H

where H: Host,

type AdviceProvider = <H as Host>::AdviceProvider

fn advice_provider(&self) -> &Self::AdviceProvider

fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider

fn get_mast_forest(&self, node_digest: &RpoDigest) -> Option<Arc<MastForest>>

fn on_debug( &mut self, process: ProcessState<'_>, options: &DebugOptions, ) -> Result<(), ExecutionError>

fn on_event( &mut self, process: ProcessState<'_>, event_id: u32, err_ctx: &ErrorContext<'_, impl MastNodeExt>, ) -> Result<(), ExecutionError>

fn on_trace( &mut self, process: ProcessState<'_>, trace_id: u32, ) -> Result<(), ExecutionError>

fn on_assert_failed(&mut self, process: ProcessState<'_>, err_code: Felt)

Implementors

impl<A: AdviceProvider> Host for DefaultHost<A>

type AdviceProvider = A