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manuel/wat-js

Concurrency and Metaprogramming for JS

Source code at GitHub https://github.com/manuel/wat-js

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  "description": "Concurrency and Metaprogramming for JS",
  "fullName": "manuel/wat-js",
  "homepage": "",
  "language": "JavaScript",
  "name": "wat-js",
  "pushedAt": "2018-01-30T17:49:16Z",
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  "updatedAt": "2025-10-07T02:47:16Z",
  "url": "https://github.com/manuel/wat-js"
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Wat

Concurrency and Metaprogramming for JS

Wat is a tiny language with powerful concurrency and metaprogramming features for embedding in JavaScript programs.

Delimited continuations http://www.cs.indiana.edu/~dyb/pubs/monadicDC.pdf
Delimited dynamic binding http://okmij.org/ftp/papers/DDBinding.pdf
First-class lexical environments and fexprs http://www.wpi.edu/Pubs/ETD/Available/etd-090110-124904/unrestricted/jshutt.pdf
First-order control (sequential, conditional, loop, throw, catch, finally) running on JS stack
Interop with JavaScript objects, functions, and callbacks
JSON-based bytecode for embedding Wat code in JavaScript

Wat is developed by Manuel Simoni (msimoni@gmail.com).

Usage

Browser

<html>
<head>
  <script type="text/javascript" unsrc="./build/wat.js"></script>
</head>
<body>
  <script type="text/javascript">
    var vm = wat.vm();
    console.log(vm.eval("(+ 1 2)"));
  </script>
</body>
</html>

Node.js

> var vm = require("./build/wat").vm();
> vm.eval("(+ 1 2)");
3

More documentation upcoming!

For now, follow http://axisofeval.blogspot.com/search/label/wat and/or https://twitter.com/msimoni for updates.