Wasm

Wasm

Efficiently execute computationally intensive tasks. Wasm module compilation, instantiation, memory management, and interaction with imports and exports.

Eg WebAssembly.instantiate, WebAssembly.Module, WebAssembly.Instance

Classes

WebAssembly.CompileError

The WebAssembly.CompileError object indicates an error during WebAssembly decoding or validation.

WebAssembly.Global

A WebAssembly.Global object represents a global variable instance, accessible from both JavaScript and importable/exportable across one or more WebAssembly.Module instances. This allows dynamic linking of multiple modules.

WebAssembly.Instance

A WebAssembly.Instance object is a stateful, executable instance of a WebAssembly.Module. Instance objects contain all the Exported WebAssembly functions that allow calling into WebAssembly code from JavaScript.

exports

WebAssembly.LinkError

The WebAssembly.LinkError object indicates an error during module instantiation (besides traps from the start function).

WebAssembly.Memory

The WebAssembly.Memory object is a resizable ArrayBuffer or SharedArrayBuffer that holds the raw bytes of memory accessed by a WebAssembly Instance.

WebAssembly.Module

A WebAssembly.Module object contains stateless WebAssembly code that has already been compiled by the browser — this can be efficiently shared with Workers, and instantiated multiple times.

WebAssembly.RuntimeError

The WebAssembly.RuntimeError object is the error type that is thrown whenever WebAssembly specifies a trap.

WebAssembly.Table

The WebAssembly.Table() object is a JavaScript wrapper object — an array-like structure representing a WebAssembly Table, which stores function references. A table created by JavaScript or in WebAssembly code will be accessible and mutable from both JavaScript and WebAssembly.

Functions

WebAssembly.compile

The WebAssembly.compile() function compiles WebAssembly binary code into a WebAssembly.Module object. This function is useful if it is necessary to compile a module before it can be instantiated (otherwise, the WebAssembly.instantiate() function should be used).

WebAssembly.compileStreaming

The WebAssembly.compileStreaming() function compiles a WebAssembly.Module directly from a streamed underlying source. This function is useful if it is necessary to a compile a module before it can be instantiated (otherwise, the WebAssembly.instantiateStreaming() function should be used).

WebAssembly.instantiate

The WebAssembly.instantiate() function allows you to compile and instantiate WebAssembly code.

WebAssembly.instantiateStreaming

The WebAssembly.instantiateStreaming() function compiles and instantiates a WebAssembly module directly from a streamed underlying source. This is the most efficient, optimized way to load wasm code.

WebAssembly.validate

The WebAssembly.validate() function validates a given typed array of WebAssembly binary code, returning whether the bytes form a valid wasm module (true) or not (false).

Interfaces

WebAssembly.GlobalDescriptor

The GlobalDescriptor describes the options you can pass to new WebAssembly.Global().

WebAssembly.MemoryDescriptor

The MemoryDescriptor describes the options you can pass to new WebAssembly.Memory().

WebAssembly.ModuleExportDescriptor

A ModuleExportDescriptor is the description of a declared export in a WebAssembly.Module.

WebAssembly.ModuleImportDescriptor

A ModuleImportDescriptor is the description of a declared import in a WebAssembly.Module.

WebAssembly.TableDescriptor

The TableDescriptor describes the options you can pass to new WebAssembly.Table().

WebAssembly.WebAssemblyInstantiatedSource

The value returned from WebAssembly.instantiate.

Namespaces

WebAssembly

The WebAssembly JavaScript object acts as the namespace for all WebAssembly-related functionality. Unlike most global objects, it is not a constructor; it groups the functions used to compile and instantiate WebAssembly modules together with the classes (Module, Instance, Memory, Table, Global) and error types used to work with them.

Type Aliases

WebAssembly.Exports

The set of values exported by a WebAssembly module instance, keyed by export name.

WebAssembly.ExportValue

A value that can be exported from a WebAssembly module instance.

WebAssembly.ImportExportKind

The kind of entity referenced by a module import or export descriptor.

WebAssembly.Imports

The import object supplied when instantiating a WebAssembly module, grouping imported values by module name.

WebAssembly.ImportValue

A value that can be supplied to a WebAssembly module as an import.

WebAssembly.ModuleImports

The set of values imported from a single module, keyed by import name.

WebAssembly.TableKind

The type of value stored in a WebAssembly.Table.

WebAssembly.ValueType

The data type of a WebAssembly value, used to describe globals.

class WebAssembly.CompileError

extends Error

The WebAssembly.CompileError object indicates an error during WebAssembly decoding or validation.

MDN

Constructors #

#CompileError(message?: string,
options?: ErrorOptions,
)

new

Creates a new WebAssembly.CompileError object.

class WebAssembly.Global

MDN

Constructors #

#Global(descriptor: GlobalDescriptor,
v?: any,
)

new

Creates a new Global object.

Properties #

#value: any

The value contained inside the global variable — this can be used to directly set and get the global's value.

Methods #

#valueOf(): any

Old-style method that returns the value contained inside the global variable.

class WebAssembly.Instance

MDN

Constructors #

#Instance(module: Module,
importObject?: Imports,
)

new

Creates a new Instance object.

Properties #

#exports: Exports

readonly

Returns an object containing as its members all the functions exported from the WebAssembly module instance, to allow them to be accessed and used by JavaScript. Read-only.

class WebAssembly.LinkError

extends Error

The WebAssembly.LinkError object indicates an error during module instantiation (besides traps from the start function).

MDN

Constructors #

#LinkError(message?: string,
options?: ErrorOptions,
)

new

Creates a new WebAssembly.LinkError object.

class WebAssembly.Memory

The WebAssembly.Memory object is a resizable ArrayBuffer or SharedArrayBuffer that holds the raw bytes of memory accessed by a WebAssembly Instance.

A memory created by JavaScript or in WebAssembly code will be accessible and mutable from both JavaScript and WebAssembly.

MDN

Constructors #

#Memory(descriptor: MemoryDescriptor)

new

Creates a new Memory object.

Properties #

#buffer: ArrayBuffer | SharedArrayBuffer

readonly

An accessor property that returns the buffer contained in the memory.

Methods #

#grow(delta: number): number

Increases the size of the memory instance by a specified number of WebAssembly pages (each one is 64KB in size).

class WebAssembly.Module

A WebAssembly.Module object contains stateless WebAssembly code that has already been compiled by the browser — this can be efficiently shared with Workers, and instantiated multiple times.

MDN

Constructors #

#Module(bytes: BufferSource)

new

Creates a new Module object.

Static Methods #

#customSections(moduleObject: Module,
sectionName: string,
): ArrayBuffer[]

Given a Module and string, returns a copy of the contents of all custom sections in the module with the given string name.

#exports(moduleObject: Module): ModuleExportDescriptor[]

Given a Module, returns an array containing descriptions of all the declared exports.

#imports(moduleObject: Module): ModuleImportDescriptor[]

Given a Module, returns an array containing descriptions of all the declared imports.

class WebAssembly.RuntimeError

extends Error

The WebAssembly.RuntimeError object is the error type that is thrown whenever WebAssembly specifies a trap.

MDN

Constructors #

#RuntimeError(message?: string,
options?: ErrorOptions,
)

new

Creates a new WebAssembly.RuntimeError object.

class WebAssembly.Table

MDN

Constructors #

#Table(descriptor: TableDescriptor)

new

Creates a new Table object.

Properties #

#length: number

readonly

Returns the length of the table, i.e. the number of elements.

Methods #

#get(index: number): Function | null

Accessor function — gets the element stored at a given index.

#grow(delta: number): number

Increases the size of the Table instance by a specified number of elements.

#set(index: number,
value: Function | null,
): void

Sets an element stored at a given index to a given value.

function WebAssembly.compile

#compile(bytes: BufferSource): Promise<Module>

MDN

Parameters #

#bytes: BufferSource

Return Type #

Promise<Module>

function WebAssembly.compileStreaming

#compileStreaming(source: Response | Promise<Response>): Promise<Module>

MDN

Parameters #

#source: Response | Promise<Response>

Return Type #

Promise<Module>

function WebAssembly.instantiate

Overload 1

#instantiate(bytes: BufferSource,
importObject?: Imports,
): Promise<WebAssemblyInstantiatedSource>

The WebAssembly.instantiate() function allows you to compile and instantiate WebAssembly code.

This overload takes the WebAssembly binary code, in the form of a typed array or ArrayBuffer, and performs both compilation and instantiation in one step. The returned Promise resolves to both a compiled WebAssembly.Module and its first WebAssembly.Instance.

MDN

Parameters #

#bytes: BufferSource

#importObject: Imports

optional

Return Type #

Promise<WebAssemblyInstantiatedSource>

Overload 2

#instantiate(moduleObject: Module,
importObject?: Imports,
): Promise<Instance>

The WebAssembly.instantiate() function allows you to compile and instantiate WebAssembly code.

This overload takes an already-compiled WebAssembly.Module and returns a Promise that resolves to an Instance of that Module. This overload is useful if the Module has already been compiled.

MDN

Parameters #

#moduleObject: Module

#importObject: Imports

optional

Return Type #

Promise<Instance>

function WebAssembly.instantiateStreaming

#instantiateStreaming(response: Response | PromiseLike<Response>,
importObject?: Imports,
): Promise<WebAssemblyInstantiatedSource>

MDN

Parameters #

#response: Response | PromiseLike<Response>

#importObject: Imports

optional

Return Type #

Promise<WebAssemblyInstantiatedSource>

function WebAssembly.validate

#validate(bytes: BufferSource): boolean

The WebAssembly.validate() function validates a given typed array of WebAssembly binary code, returning whether the bytes form a valid wasm module (true) or not (false).

MDN

Parameters #

#bytes: BufferSource

Return Type #

boolean

interface WebAssembly.GlobalDescriptor

The GlobalDescriptor describes the options you can pass to new WebAssembly.Global().

Properties #

#mutable: boolean

optional

Whether the global variable can be modified after creation. Defaults to false.

#value: ValueType

The data type of the global variable.

interface WebAssembly.MemoryDescriptor

The MemoryDescriptor describes the options you can pass to new WebAssembly.Memory().

Properties #

#initial: number

The initial size of the memory, in units of WebAssembly pages (64KB each).

#maximum: number

optional

The maximum size the memory is allowed to grow to, in units of WebAssembly pages.

#shared: boolean

optional

Whether the memory is shared between agents (backed by a SharedArrayBuffer). Defaults to false.

interface WebAssembly.ModuleExportDescriptor

A ModuleExportDescriptor is the description of a declared export in a WebAssembly.Module.

Properties #

#kind: ImportExportKind

The kind of entity being exported.

#name: string

The name under which the entity is exported.

interface WebAssembly.ModuleImportDescriptor

A ModuleImportDescriptor is the description of a declared import in a WebAssembly.Module.

Properties #

#kind: ImportExportKind

The kind of entity being imported.

#module: string

The name of the module the entity is imported from.

#name: string

The name of the imported entity within its module.

interface WebAssembly.TableDescriptor

The TableDescriptor describes the options you can pass to new WebAssembly.Table().

Properties #

#element: TableKind

The type of value stored in the table.

#initial: number

The initial number of elements in the table.

#maximum: number

optional

The maximum number of elements the table is allowed to grow to.

interface WebAssembly.WebAssemblyInstantiatedSource

The value returned from WebAssembly.instantiate.

Properties #

#instance: Instance

A WebAssembly.Instance object that contains all the exported WebAssembly functions.

#module: Module

A WebAssembly.Module object representing the compiled WebAssembly module. This Module can be instantiated again, or shared via postMessage().

namespace WebAssembly

MDN

Classes #

WebAssembly.CompileError

The WebAssembly.CompileError object indicates an error during WebAssembly decoding or validation.

WebAssembly.Global

WebAssembly.Instance

exports

WebAssembly.LinkError

The WebAssembly.LinkError object indicates an error during module instantiation (besides traps from the start function).

WebAssembly.Memory

The WebAssembly.Memory object is a resizable ArrayBuffer or SharedArrayBuffer that holds the raw bytes of memory accessed by a WebAssembly Instance.

WebAssembly.Module

A WebAssembly.Module object contains stateless WebAssembly code that has already been compiled by the browser — this can be efficiently shared with Workers, and instantiated multiple times.

WebAssembly.RuntimeError

The WebAssembly.RuntimeError object is the error type that is thrown whenever WebAssembly specifies a trap.

WebAssembly.Table

Functions #

WebAssembly.compile

WebAssembly.compileStreaming

WebAssembly.instantiate

The WebAssembly.instantiate() function allows you to compile and instantiate WebAssembly code.

WebAssembly.instantiateStreaming

WebAssembly.validate

The WebAssembly.validate() function validates a given typed array of WebAssembly binary code, returning whether the bytes form a valid wasm module (true) or not (false).

Interfaces #

WebAssembly.GlobalDescriptor

The GlobalDescriptor describes the options you can pass to new WebAssembly.Global().

WebAssembly.MemoryDescriptor

The MemoryDescriptor describes the options you can pass to new WebAssembly.Memory().

WebAssembly.ModuleExportDescriptor

A ModuleExportDescriptor is the description of a declared export in a WebAssembly.Module.

WebAssembly.ModuleImportDescriptor

A ModuleImportDescriptor is the description of a declared import in a WebAssembly.Module.

WebAssembly.TableDescriptor

The TableDescriptor describes the options you can pass to new WebAssembly.Table().

WebAssembly.WebAssemblyInstantiatedSource

The value returned from WebAssembly.instantiate.

Type Aliases #

WebAssembly.Exports

The set of values exported by a WebAssembly module instance, keyed by export name.

WebAssembly.ExportValue

A value that can be exported from a WebAssembly module instance.

WebAssembly.ImportExportKind

The kind of entity referenced by a module import or export descriptor.

WebAssembly.Imports

The import object supplied when instantiating a WebAssembly module, grouping imported values by module name.

WebAssembly.ImportValue

A value that can be supplied to a WebAssembly module as an import.

WebAssembly.ModuleImports

The set of values imported from a single module, keyed by import name.

WebAssembly.TableKind

The type of value stored in a WebAssembly.Table.

WebAssembly.ValueType

The data type of a WebAssembly value, used to describe globals.

type alias WebAssembly.Exports

The set of values exported by a WebAssembly module instance, keyed by export name.

Definition #

Record<string, ExportValue>

type alias WebAssembly.ExportValue

A value that can be exported from a WebAssembly module instance.

Definition #

Function
 | Global
 | Memory
 | Table

type alias WebAssembly.ImportExportKind

The kind of entity referenced by a module import or export descriptor.

Definition #

"function"
 | "global"
 | "memory"
 | "table"

type alias WebAssembly.Imports

The import object supplied when instantiating a WebAssembly module, grouping imported values by module name.

Definition #

Record<string, ModuleImports>

type alias WebAssembly.ImportValue

A value that can be supplied to a WebAssembly module as an import.

Definition #

ExportValue | number

type alias WebAssembly.ModuleImports

The set of values imported from a single module, keyed by import name.

Definition #

Record<string, ImportValue>

type alias WebAssembly.TableKind

The type of value stored in a WebAssembly.Table.

Definition #

"anyfunc"

type alias WebAssembly.ValueType

The data type of a WebAssembly value, used to describe globals.

Definition #

"f32"
 | "f64"
 | "i32"
 | "i64"