Struct wasmer_types::Features

pub struct Features {
    pub threads: bool,
    pub reference_types: bool,
    pub simd: bool,
    pub bulk_memory: bool,
    pub multi_value: bool,
    pub tail_call: bool,
    pub module_linking: bool,
    pub multi_memory: bool,
    pub memory64: bool,
    pub exceptions: bool,
    pub relaxed_simd: bool,
    pub extended_const: bool,
}

Controls which experimental features will be enabled. Features usually have a corresponding WebAssembly proposal.

Fields

threads: bool

Threads proposal should be enabled

reference_types: bool

Reference Types proposal should be enabled

simd: bool

SIMD proposal should be enabled

bulk_memory: bool

Bulk Memory proposal should be enabled

multi_value: bool

Multi Value proposal should be enabled

tail_call: bool

Tail call proposal should be enabled

module_linking: bool

Module Linking proposal should be enabled

multi_memory: bool

Multi Memory proposal should be enabled

memory64: bool

64-bit Memory proposal should be enabled

exceptions: bool

Wasm exceptions proposal should be enabled

relaxed_simd: bool

Relaxed SIMD proposal should be enabled

extended_const: bool

Extended constant expressions proposal should be enabled

Implementations

impl Features

pub fn new() -> Self

Create a new feature

pub fn threads(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly threads proposal will be enabled.

The WebAssembly threads proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature gates items such as shared memories and atomic instructions.

This is false by default.

pub fn reference_types(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly reference types proposal will be enabled.

The WebAssembly reference types proposal is now fully standardized and enabled by default.

This feature gates items such as the externref type and multiple tables being in a module. Note that enabling the reference types feature will also enable the bulk memory feature.

This is true by default.

pub fn simd(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly SIMD proposal will be enabled.

The WebAssembly SIMD proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature gates items such as the v128 type and all of its operators being in a module.

This is false by default.

pub fn bulk_memory(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly bulk memory operations proposal will be enabled.

The WebAssembly bulk memory operations proposal is now fully standardized and enabled by default.

This feature gates items such as the memory.copy instruction, passive data/table segments, etc, being in a module.

This is true by default.

pub fn multi_value(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly multi-value proposal will be enabled.

The WebAssembly multi-value proposal is now fully standardized and enabled by default, except with the singlepass compiler which does not support it.

This feature gates functions and blocks returning multiple values in a module, for example.

This is true by default.

pub fn tail_call(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly tail-call proposal will be enabled.

The WebAssembly tail-call proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature gates tail-call functions in WebAssembly.

This is false by default.

pub fn module_linking(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly module linking proposal will be enabled.

The WebAssembly module linking proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature allows WebAssembly modules to define, import and export modules and instances.

This is false by default.

pub fn multi_memory(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly multi-memory proposal will be enabled.

The WebAssembly multi-memory proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature adds the ability to use multiple memories within a single Wasm module.

This is false by default.

pub fn memory64(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly 64-bit memory proposal will be enabled.

The WebAssembly 64-bit memory proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This feature gates support for linear memory of sizes larger than 2^32 bits.

This is false by default.

pub fn exceptions(&mut self, enable: bool) -> &mut Self

Configures whether the WebAssembly exception-handling proposal will be enabled.

The WebAssembly exception-handling proposal is not currently fully standardized and is undergoing development. Support for this feature can be enabled through this method for appropriate WebAssembly modules.

This is false by default.

pub fn contains_features(&self, required: &Self) -> bool

Checks if this features set contains all the features required by another set

pub fn detect_from_wasm(wasm_bytes: &[u8]) -> Result<Self, BinaryReaderError>

Detects required WebAssembly features from a module binary.

This method analyzes a WebAssembly module’s binary to determine which features it requires. It does this by:

1. Attempting to validate the module with different feature sets
2. Analyzing validation errors to detect required features
3. Parsing the module to detect certain common patterns

Arguments

• wasm_bytes - The binary content of the WebAssembly module

Returns

A new Features instance with the detected features enabled.

Trait Implementations

impl Archive for Features

where bool: Archive,

type Archived = ArchivedFeatures

The archived representation of this type.

type Resolver = FeaturesResolver

The resolver for this type. It must contain all the additional information from serializing needed to make the archived type from the normal type.

const COPY_OPTIMIZATION: CopyOptimization<Self> = _

An optimization flag that allows the bytes of this type to be copied directly to a writer instead of calling serialize.

fn resolve(&self, resolver: Self::Resolver, out: Place<Self::Archived>)

Creates the archived version of this value at the given position and writes it to the given output.

impl Clone for Features

fn clone(&self) -> Features

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Features

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

Formats the value using the given formatter.

impl Default for Features

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Features

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<__D: Fallible + ?Sized> Deserialize<Features, __D> for Archived<Features>

where bool: Archive, <bool as Archive>::Archived: Deserialize<bool, __D>,

fn deserialize( &self, deserializer: &mut __D, ) -> Result<Features, <__D as Fallible>::Error>

Deserializes using the given deserializer

impl PartialEq<ArchivedFeatures> for Features

where bool: Archive, <bool as Archive>::Archived: PartialEq<bool>,

fn eq(&self, other: &ArchivedFeatures) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq<Features> for ArchivedFeatures

where bool: Archive, <bool as Archive>::Archived: PartialEq<bool>,

fn eq(&self, other: &Features) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialEq for Features

fn eq(&self, other: &Features) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<__S: Fallible + ?Sized> Serialize<__S> for Features

where bool: Serialize<__S>,

fn serialize( &self, serializer: &mut __S, ) -> Result<<Self as Archive>::Resolver, <__S as Fallible>::Error>

Writes the dependencies for the object and returns a resolver that can create the archived type.

impl Serialize for Features

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Features

impl StructuralPartialEq for Features