js-inline-wat

A tool for bundling a WebAssembly .wat file into a .js ES6 library file.

Installation

npm install -D js-inline-wat

Usage

$ inlinewat sample.wat [-o sample.wat.js] [-t decoded]

In package.json

scripts: {
    "inlinewat": "inlinewat wat/sample.wat -o build/sample.js"
}

Options

• --input file The .wat file to inline

• -o, --output file The .js file to create

• -t, --type typeName The type of JavaScript file to generate - "decoded" (default), "encoded", "fetch"

• -h, --help Show this Help page

Types

Each type outputs a different variant of JavaScript file

-type fetch

Creates a JavaScript file with a default export function that can be used anywhere you could use fetch(). e.g.

import fetchSample from 'sample'; // sample.js contains the bundled .wat

WebAssembly.instantiateStreaming(fetchSample)
    .then(obj => obj.instance.exports.exported_func());

-type decoded

Creates a JavaScript file with a default export byte array containing the decoded .wat content

Note: You'll probably want to use WebAssembly.instantiateStreaming() in most cases, as it is more efficient than instantiate().

import decodedSample from 'sample'; // sample.js contains the bundled .wat

WebAssembly.instantiate(decodedSample)
    .then(obj => obj.instance.exports.exported_func());

-type encoded

Creates a JavaScript file with a default export string value containing the base64 encoded .wat file

import encodedSample from 'sample'; // sample.js contains the bundled .wat

// Decode the base64 string then compile...