Using Dusa in your JavaScript programs

As Julia Evans describes, in 2024 there are basically three ways use JavaScript code in your project.

1. A “classic” module that just defines a global variable
2. An ES module
3. Use a build system

Classic modules

To use Dusa in your random web page, include the UMD module in a script tag in the head of your file, for example with unpkg like this:

<script
  src="https://unpkg.com/dusa@0.1.6"
  integrity="sha384-dQ1a/faivdqPhpQcxYG+tCkmln6OAQAi5gccaliGtbeOcGFGgXlsLuSKl+h8Jp8r"
  crossorigin="anonymous"
></script>

or with jsdelivr like this:

<script
  src="https://cdn.jsdelivr.net/npm/dusa@0.1.6"
  integrity="sha384-rz5oQihX+60VISoW9hKtiHrEU11ydb3dfTN93lQEAIx0XwNOEfR3z3jFaYieGfrp"
  crossorigin="anonymous"
></script>

This defines the Dusa name, which can be used to make new Dusa classes or access the various helpers.

const dusa = new Dusa('fact is { mortal socrates, man socrates }.');
function handleClick() {
  const fact = Dusa.termToString(dusa.sample().get('fact'));
  document.getElementById('facts').innerText = fact;
}

• Example 1: Glitch site
• Example 2: p5js sketch

ES modules

ES modules can be used to access the Dusa class and the helpers in any development using ES modules, without requiring any build system.

import { Dusa, termToString } from 'https://unpkg.com/dusa@0.1.6/lib/client.js';
const dusa = new Dusa('fact is { mortal socrates, man socrates }.');
console.log(termToString(dusa.solution.get('fact')));

The val.town examples used elsewhere in the docs use this way of importing Dusa. Here’s the example above on val.town.

Build system imports

If import dusa through NPM (or a similar package manager/build system), then you can import the core Dusa class as well as the helpers through the 'dusa' import.

example.mjs

import { Dusa, termToString } from 'dusa';
const dusa = new Dusa('fact is { mortal socrates, man socrates }.');
console.log(termToString(dusa.solution.get('fact')));

example.cjs

const { Dusa, termToString } = require('dusa');
const dusa = new Dusa('fact is { mortal socrates, man socrates }.');
console.log(termToString(dusa.solution.get('fact')));