# parcel
***
**1. Basic Parcel Configuration**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {});
bundler.bundle();
```
**2. Using a Custom Output Path**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {
outFile: 'dist/index.html',
});
bundler.bundle();
```
**3. Serving Static Files**
```js
const express = require('express');
const { ParcelMiddleware } = require('parcel-bundler');
const app = express();
app.use(ParcelMiddleware({
publicUrl: '/',
outDir: './dist',
}));
app.listen(3000);
```
**4. Including CSS and JS**
```html
```
**5. Using Tailwind.css with Parcel**
```js
const { ParcelConfig } = require('parcel-bundler');
const tailwindcss = require('tailwindcss');
const postcss = require('postcss');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('css', async function (source, options) {
const result = await postcss([tailwindcss()]).process(source);
return result.css;
});
```
**6. Building a Production Bundle**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {
env: 'production',
});
bundler.bundle();
```
**7. Using a Polyfill**
```js
const { ParcelConfig } = require('parcel-bundler');
const autoprefixer = require('autoprefixer');
const postcss = require('postcss');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('css', async function (source, options) {
const result = await postcss([autoprefixer()]).process(source);
return result.css;
});
```
**8. Bundling SVGs**
```html
```
**9. Using Babel**
```js
const { ParcelConfig } = require('parcel-bundler');
const babelCore = require('@babel/core');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('js', async function (source, options) {
const result = await babelCore.transformAsync(source, { presets: ['@babel/preset-env'] });
return result.code;
});
```
**10. Using TypeScript**
```js
const { ParcelConfig } = require('parcel-bundler');
const ts = require('typescript');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('ts', async function (source, options) {
const result = ts.transpile(source);
return result;
});
```
**11. Bundling JSON**
```html
```
**12. Using a Custom Plugin**
```js
const { ParcelBundler, transformers } = require('parcel-bundler');
const MyPlugin = {
apply(bundler) {
bundler.addAssetType('.my-extension', transformers.raw);
},
};
const bundler = new ParcelBundler('index.html', { plugins: [MyPlugin] });
```
**13. Watching for File Changes**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', { watch: true });
bundler.bundle();
```
**14. Using a Custom Cache Directory**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', { cacheDir: './my-cache' });
bundler.bundle();
```
**15. Using a Custom Resolver**
```js
const { ParcelConfig } = require('parcel-bundler');
const { NodeResolver } = require('@parcel/node-resolver');
const parcelConfig = new ParcelConfig();
parcelConfig.resolvers.unshift(new NodeResolver({ root: './node_modules' }));
```
**16. Using a Custom Query String**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {
query: 'development=true',
});
bundler.bundle();
```
**17. Using a Custom URL Prefix**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {
publicUrl: '//cdn.example.com',
});
bundler.bundle();
```
**18. Using a Custom Source Map**
```js
const { ParcelBundler } = require('parcel-bundler');
const bundler = new ParcelBundler('index.html', {
sourceMaps: true,
});
bundler.bundle();
```
**19. Using a Custom Transform**
```js
const { ParcelConfig } = require('parcel-bundler');
const { Transform } = require('stream');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('js', async function (source, options) {
return new Transform({
transform(chunk, encoding, callback) {
callback(null, chunk.toString().toUpperCase());
},
});
});
```
**20. Using a Custom Webpack Loader**
```js
const { ParcelConfig } = require('parcel-bundler');
const { WebpackLoader } = require('@parcel/webpack-loader');
const parcelConfig = new ParcelConfig();
parcelConfig.addTransformer('js', new WebpackLoader({
loaders: [
{
loader: 'babel-loader',
options: {
presets: ['@babel/preset-env']
```