Struct wasmer::Instance

pub struct Instance {
    pub exports: Exports,
    // some fields omitted
}

A WebAssembly Instance is a stateful, executable instance of a WebAssembly Module.

Instance objects contain all the exported WebAssembly functions, memories, tables and globals that allow interacting with WebAssembly.

Spec: https://webassembly.github.io/spec/core/exec/runtime.html#module-instances

Fields

exports: Exports

The exports for an instance.

Implementations

impl Instance

pub fn new(
    module: &Module,
    resolver: &dyn Resolver
) -> Result<Self, InstantiationError>

Creates a new Instance from a WebAssembly Module and a set of imports resolved by the Resolver.

The resolver can be anything that implements the Resolver trait, so you can plug custom resolution for the imports, if you wish not to use ImportObject.

The ImportObject is the easiest way to provide imports to the instance.

let store = Store::default();
let module = Module::new(&store, "(module)")?;
let imports = imports!{
  "host" => {
    "var" => Global::new(&store, Value::I32(2))
  }
};
let instance = Instance::new(&module, &imports)?;

Errors

The function can return InstantiationErrors.

Those are, as defined by the spec:

• Link errors that happen when plugging the imports into the instance
• Runtime errors that happen when running the module start function.

pub fn new_with_config(
    module: &Module,
    config: InstanceConfig,
    resolver: &dyn Resolver
) -> Result<Self, InstantiationError>

New instance with config.

pub fn module(&self) -> &Module

Gets the Module associated with this instance.

pub fn store(&self) -> &Store

Returns the Store where the Instance belongs.

Trait Implementations

impl Clone for Instance

fn clone(&self) -> Instance

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Instance

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

Formats the value using the given formatter.

impl MemoryUsage for Instance

fn size_of_val(&self, visited: &mut dyn MemoryUsageTracker) -> usize

Returns the size of the referenced value in bytes.