swipl-wasm

swipl-wasm

SWI-Prolog WebAssembly build as a NPM package. Please see this page for ongoing progress and information: https://swi-prolog.discourse.group/t/swi-prolog-in-the-browser-using-wasm/5650

Usage

In browser:

<div id="solution"></div>
<script src="/dist/swipl/swipl-web.js"></script>
<script>
  (async () => {
    const swipl = await SWIPL({
      noInitialRun: true,
      arguments: ["-q"],
      locateFile: (url) => {
        if (url === "swipl-web.data") {
          return "/dist/swipl/swipl-web.data";
        } else if (url === "swipl-web.wasm") {
          return "/dist/swipl/swipl-web.wasm";
        }
        return url;
      },
    });
    const query = "member(X, [a, b, c]).";
    const solutionElement = document.getElementById("solution");
    // See https://swi-prolog.discourse.group/t/swi-prolog-in-the-browser-using-wasm/5650/1
    const firstSolution = swipl.prolog.query(query).once().X;
    solutionElement.textContent = firstSolution;
  })();
</script>

You can run this example by executing npm run test:serve-http and visiting http://localhost:8080/examples/browser.html.

In Nodejs:

// This helps to find the correct locations of the
// .data and .wasm files.
const swiplModuleLocation = require.resolve("swipl-wasm/swipl");
const swipl = await SWIPL({
  noInitialRun: true,
  arguments: ["-q"],
  locateFile: (url) => {
    // These are common with the web version.
    if (url === "swipl-web.data") {
      return path.join(path.dirname(swiplModuleLocation), "swipl-web.data");
    } else if (url === "swipl-web.wasm") {
      return path.join(path.dirname(swiplModuleLocation), "swipl-web.wasm");
    }
    return url;
  },
});
// See https://swi-prolog.discourse.group/t/swi-prolog-in-the-browser-using-wasm/5650/1
console.log(swipl.prolog.query("member(X, [a, b, c]).").once().X);

You can run this example with node examples/run-on-node.js.

Build

The package can be built using npm or yarn. Please use yarn to add new dependencies and update yarn.lock file. SWI-Prolog WebAssembly version is currently built inside Docker with Emscripten.

TODO

• More examples (how to bundle with webpack)
• Integrate with SWI-Prolog CI
• TypeScript types for Prolog.js (and the Query interface)
• Use EcmaScript modules as output: https://github.com/emscripten-core/emscripten/issues/11792

License

Same as SWI-Prolog license, BSD simplified: https://github.com/SWI-Prolog/swipl-devel/blob/master/LICENSE