swift-js

0.1.0 verified Fri May 01 auth: no javascript abandoned

A Swift-to-JavaScript transpiler (v0.1.0) that converts a subset of Swift syntax into JavaScript. Provides basic support for classes, functions, variables, and control flow. Not actively maintained; experimental status. Differentiators vs alternative transpilers (e.g., Kotlin/JS, Scala.js) include minimal dependencies and a simple CLI workflow, but lacks robust error handling, Unicode support, and standard library mapping. Suitable for proof-of-concept projects only.

Common errors

error Cannot find module 'swift-js' ↓

cause Package not installed or not in a valid npm registry.

fix

Install via 'npm install swift-js' from npm registry.

error 'require' is not defined in ES module scope ↓

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

fix

Use 'import { transpile } from 'swift-js';' or set 'type': 'module' in package.json.

error Unexpected token: '(' ↓

cause Swift syntax not supported by the transpiler (e.g., closures with shorthand arguments).

fix

Rewrite unsupported Swift constructs using basic function definitions.

Warnings

gotcha Swift string interpolation escaped incorrectly in JavaScript output. ↓

fix Manually replace \(...) with template literal syntax ${...} after transpilation.

gotcha Does not support Swift's Optional types; nil may be mapped to undefined incorrectly. ↓

fix Handle undefined values manually in generated JS code.

deprecated Package has not been updated since 2020; consider using modern alternatives like Kotlin/JS or TypeScript. ↓

fix Migrate to a supported transpiler.

Install

npm install swift-js

yarn add swift-js

pnpm add swift-js

Imports

transpile
wrong
```
const swift = require('swift-js');
```
correct
```
import { transpile } from 'swift-js';
```
ESM-only support; CJS require() fails due to missing default export.
default
wrong
```
const swiftjs = require('swift-js').default;
```
correct
```
import swiftjs from 'swift-js';
```
Default export is the transpile function; named export also available.

SwiftJSTranspiler

wrong

const Transpiler = require('swift-js').SwiftJSTranspiler;

correct

import { SwiftJSTranspiler } from 'swift-js';

Class export for advanced usage; requires ESM import.

Quickstart

Basic example transpiling a Swift function to JavaScript, including error handling for transpilation failures.

import { transpile } from 'swift-js';

const swiftCode = `
func greet(name: String) -> String {
    return "Hello, \(name)!"
}
print(greet(name: "World"))
`;

try {
  const jsCode = transpile(swiftCode);
  console.log(jsCode);
} catch (err) {
  console.error('Transpilation error:', err.message);
}