Cannot find modules

Bug Report

Overview

I get the error, TypeError: WebAssembly Instantiation: Import #0 module="utils" error: module is not an object or function. I assume there is something I need to do to make these available, but I could not find anything in the docs.

Expected

Should import modules like log from the env module, as shown in the simple Walt Explorer examples and quick start guide.

Actual

TypeError - can’t resolve modules.

Example

Versions

Node.js: v8.10 Webpack: 4.15.1 walt-loader: 1.0.21

import { log: LogType } from 'env'; // also tried 'console' here
type LogType = (i32) => void;

Webpack config:

const path = require('path')

module.exports = {
  resolve: {
    extensions: [".walt", ".js", ".css"]
  },
  module: {
    rules: [
      { test: /\.walt$/, use: 'walt-loader' },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: "babel-loader"
      },
      { test: /\.css$/, use: ['style-loader', 'css-loader'] }
    ]
  },
  entry: './src/index.js',
  output: {
    filename: 'bundle.js',
    path: path.resolve(__dirname, 'dist')
  }
}

[ballercat]

It still runs int the JavaScript sandbox, think of it as if you linked a .dll into your executable. You can call the methods imported but you don’t change how they are written/executed.

There is even a slight penalty for crossing that wasm <> js boundary (in either direction) as the engine has to perform validation and security(?) checks. I think Firefox at least has worked around some of these speed bumps though.

[njtrettel]

@ballercat didn’t want to open a new issue for this, because it’s just a random question. a response is not urgent.

if i were to import a javascript library to use in walt (such as importing console.log in your example), would the performance be the same as if i ran it in JS? i.e, these imported JS library are still run in a JS environment right? I would assume so.

thinking wishfully - It would be super cool if I could import something like lodash and have it perform like WASM.