Woxi

An interpreter for a subset of the Wolfram Language powered by Rust and compiled to WebAssembly.

This package wraps the Woxi interpreter so it can be used from Node.js — no Wolfram installation required. Woxi is a computer algebra system (CAS): computations are solved symbolically.

Installation

npm install woxi-wasm

(The package is named woxi-wasm because the name woxi is not available on npm.)

Usage

import { evaluate } from "woxi-wasm"

evaluate("Plus[1, 2]")        //=> "3"
evaluate("1/3 + 1/6")         //=> "1/2"
evaluate("Sqrt[8]")           //=> "2*Sqrt[2]"
evaluate('StringReverse["hello"]')  //=> "olleh"

CommonJS works too:

const { evaluate } = require("woxi-wasm")

Interpreter state (variables, function definitions) persists across calls:

import woxi from "woxi-wasm"

woxi.evaluate("f[x_] := x^2")
woxi.evaluate("f[5]")  //=> "25"
woxi.clear()           // reset all state

Structured output

evaluateAll returns one item per output, including graphics as SVG:

const items = woxi.evaluateAll('Print["hi"]\nGraphics[{Disk[]}]')
//=> [
//     { type: "print", text: "hi" },
//     { type: "graphics", svg: "<svg …" },
//   ]

Item types: text, print, graphics, warning, error, sound, and manipulate.

Virtual files

There is no filesystem access from WebAssembly, so Import[…] reads from an in-memory store you populate first:

woxi.setVirtualFile("data.csv", "a,b\n1,2\n")
woxi.evaluate('Import["data.csv"]')  //=> "{{a, b}, {1, 2}}"

Import["https://…"] fetches over HTTP automatically.

API

| Function | Description | |------------------------------|---------------------------------------------------| | evaluate(code) | Evaluate code, return output as a string | | evaluateAll(code) | Evaluate code, return structured output items | | splitStatements(code) | Split code into top-level statements | | evaluateStatement(stmt) | Evaluate a single statement (structured output) | | getGraphics() | SVG captured by the last evaluate() call | | getSound() | Base64 audio captured by the last call | | getWarnings() | Warnings of the last call as an array | | clear() | Clear all interpreter state | | setDarkMode(enabled) | Toggle dark-mode colors for SVG output | | setVirtualFile(name, data) | Register an in-memory file for Import[…] | | clearVirtualFiles() | Remove all registered in-memory files |

TypeScript definitions are included.

Development

The wasm bundle in pkg/ is generated from the Rust sources — build it from the repository root:

make npm-build   # build pkg/ with wasm-pack
make npm-test    # build + run the JS test suite

License

AGPL-3.0-or-later