What is @swc-node/core?
@swc-node/core is a Node.js binding for the SWC (Speedy Web Compiler) project, which is a super-fast TypeScript/JavaScript compiler written in Rust. It allows you to transform and compile TypeScript and JavaScript code with high performance.
What are @swc-node/core's main functionalities?
Transforming Code
This feature allows you to transform TypeScript or JavaScript code into JavaScript. The `transformSync` function takes the source code and an options object, and returns the transformed code.
const { transformSync } = require('@swc-node/core');
const output = transformSync('const x: number = 1;', { jsc: { parser: { syntax: 'typescript' } } });
console.log(output.code);
Compiling Code
This feature allows you to compile TypeScript or JavaScript code asynchronously. The `compile` function takes the source code and an options object, and returns a promise that resolves to the compiled code.
const { compile } = require('@swc-node/core');
compile('const x: number = 1;', { jsc: { parser: { syntax: 'typescript' } } }).then(output => {
console.log(output.code);
});
Using with Node.js
This feature allows you to use SWC with Node.js directly. By requiring `@swc-node/register`, you can run TypeScript code in Node.js without pre-compiling it.
require('@swc-node/register');
const x: number = 1;
console.log(x);
Other packages similar to @swc-node/core
typescript
TypeScript is a language for application-scale JavaScript. It includes a compiler that can compile TypeScript code to JavaScript. Compared to @swc-node/core, TypeScript's compiler is slower but offers more comprehensive type-checking and language features.
babel
Babel is a JavaScript compiler that allows you to use next-generation JavaScript, today. It can transform syntax, polyfill features that are missing in your target environment, and more. Babel is more feature-rich but slower compared to @swc-node/core.
esbuild
esbuild is an extremely fast JavaScript bundler and minifier. It supports TypeScript and modern JavaScript syntax out of the box. esbuild is comparable to @swc-node/core in terms of speed but focuses more on bundling and minification.
@swc-node/core
Benchmark
transform AjaxObservable.ts to ES2015 & CommonJS JavaScript
.
@swc-node/core x 151 ops/sec ±3.74% (77 runs sampled)
@swc/core x 107 ops/sec ±0.51% (78 runs sampled)
esbuild x 52.89 ops/sec ±1.58% (67 runs sampled)
typescript x 21.08 ops/sec ±9.68% (40 runs sampled)
Transform rxjs/AjaxObservable.ts benchmark bench suite: Fastest is @swc-node/core
Usage
export interface Options {
target?: 'es3' | 'es5' | 'es2015' | 'es2016' | 'es2017' | 'es2018' | 'es2019' | 'es2020'
module?: 'commonjs' | 'umd' | 'amd' | 'es6'
sourcemap?: boolean | 'inline'
experimentalDecorators?: boolean
emitDecoratorMetadata?: boolean
dynamicImport?: boolean
}
export function transformSync(
source: string | Buffer,
path: string,
options?: Options,
): {
code: string
map: string
}
export function transform(
source: string | Buffer,
path: string,
options?: Options,
): Promise<{
code: string
map: string
}>