eo2js

0.0.8 verified Fri May 01 auth: no javascript

eo2js is a transpiler that converts EOLANG (EO) programs to JavaScript, enabling execution in Node.js and browser environments. Current version 0.0.8 is pre-1.0 with active development. It translates EO objects and contracts into equivalent JS classes and functions, preserving the purely object-oriented paradigm. Unlike general transpilers, it is purpose-built for EO's abstract object model, including attributes, dataization, and runtime type checking. Release cadence is irregular; frequent breaking changes expected. Differentiators: native EO-to-JS mapping, minimal runtime, and support for EO's freeze/lock semantics.

Common errors

error Error: Cannot find module 'eo2js' ↓

cause Package is not installed or import path incorrect.

fix

Run npm install eo2js and ensure you are using ESM import syntax (not require).

error SyntaxError: Unexpected token 'export' ↓

cause Using CommonJS require() with an ESM-only package.

fix

Change to import statement and use .mjs file extension or 'type':'module' in package.json.

error TypeError: eo2js is not a function ↓

cause Default import used when package only provides named exports.

fix

Use import { compile } from 'eo2js' or import * as eo2js from 'eo2js' and call eo2js.compile().

Warnings

breaking API changes between minor versions: eo2js function signature changed in 0.0.5 from (code, options) to (source, options). ↓

fix Update calls to use new parameter order: eo2js(source, options)

breaking Default export removed in 0.0.7; use named exports like compile instead. ↓

fix import { compile } from 'eo2js' instead of import eo2js from 'eo2js'

gotcha Transpiled JS requires eolang runtime to execute; not standalone. ↓

fix Ensure eolang package is installed and imported before executing transpiled code

deprecated Options.target deprecated since 0.0.6; use options.platform instead. ↓

fix Replace target with platform in options object

Install

npm install eo2js

yarn add eo2js

pnpm add eo2js

Imports

eo2js
wrong
```
const eo2js = require('eo2js')
```
correct
```
import eo2js from 'eo2js'
```
Package uses ESM only; CJS require will fail with ERR_REQUIRE_ESM

compile

wrong

import compile from 'eo2js'

correct

import { compile } from 'eo2js'

compile is a named export, not default

Package
```
import { Package } from 'eo2js'
```
Used for object composition; available since 0.0.5

Quickstart

This code transpiles a simple EO program to JavaScript and executes it using the eolang runtime.

import eo2js from 'eo2js';

// Sample EO program
const eoCode = `
[] > main
  "Hello, EO!" > msg
  QQ.io.stdout > @
    msg
    \n
`;

try {
  const jsCode = eo2js(eoCode, { target: 'node' });
  console.log('Transpiled JS:');
  console.log(jsCode);
  // Execute the generated JS (requires eolang runtime)
  const { evaluate } = await import('eolang');
  const result = await evaluate(jsCode);
  console.log('Output:', result);
} catch (err) {
  console.error('Transpilation failed:', err);
}