class WASI
Usage in Deno
```typescript import { WASI } from "node:node__wasi.d.ts"; ```> [!WARNING] Deno compatibility
> This symbol is a non-functional stub.
The `WASI` class provides the WASI system call API and additional convenience
methods for working with WASI-based applications. Each `WASI` instance
represents a distinct environment.
new
WASI(options?: WASIOptions)
readonly
wasiImport: Dict<any>
`wasiImport` is an object that implements the WASI system call API. This object
should be passed as the `wasi_snapshot_preview1` import during the instantiation
of a [`WebAssembly.Instance`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/Instance).
getImportObject(): object
Return an import object that can be passed to `WebAssembly.instantiate()` if no other WASM imports are needed beyond those provided by WASI.
If version `unstable` was passed into the constructor it will return:
```js
{ wasi_unstable: wasi.wasiImport }
```
If version `preview1` was passed into the constructor or no version was specified it will return:
```js
{ wasi_snapshot_preview1: wasi.wasiImport }
```
initialize(instance: object): void
Attempt to initialize `instance` as a WASI reactor by invoking its `_initialize()` export, if it is present. If `instance` contains a `_start()` export, then an exception is thrown.
`initialize()` requires that `instance` exports a [`WebAssembly.Memory`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/Memory) named `memory`.
If `instance` does not have a `memory` export an exception is thrown.
If `initialize()` is called more than once, an exception is thrown.
start(instance: object): number
Attempt to begin execution of `instance` as a WASI command by invoking its `_start()` export. If `instance` does not contain a `_start()` export, or if `instance` contains an `_initialize()`
export, then an exception is thrown.
`start()` requires that `instance` exports a [`WebAssembly.Memory`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WebAssembly/Memory) named `memory`. If
`instance` does not have a `memory` export an exception is thrown.
If `start()` is called more than once, an exception is thrown.