**6to5** turns ES6 code into vanilla ES5, so you can use ES6 features **today.**
- **Fast** - [10x faster than Traceur](#performance).
- **Extensive** - with Browserify support, Node API, Connect Middleware and a CLI.
- **Lossless** - source map support so you can debug your compiled code with ease.
- **Compact** - maps directly to the equivalent ES5 with **no runtime required**.
- **Concise** - does not pollute scope with unneccesary variables.
## Features
| Name | Implemented |
| -------------------------------------------------------------------- | ----------- |
| [Arrow functions](FEATURES.md#arrow-functions) | ✓ |
| [Classes](FEATURES.md#classes) | ✓ |
| [Default parameters](FEATURES.md#default-parameters) | ✓ |
| [Spread](FEATURES.md#spread) | ✓ |
| [Block binding](FEATURES.md#block-binding) | ✓ |
| [Property method assignment](FEATURES.md#property-method-assignment) | ✓ |
| [Rest parameters](FEATURES.md#rest-parameters) | ✓ |
| [Template literals](FEATURES.md#template-literals) | ✓ |
| [Modules](FEATURES.md#modules) | ✓ |
| [Property name shorthand](FEATURES.md#property-name-shorthand) | ✓ |
| [Computed property names](FEATURES.md#computed-property-names) | ✓ |
| [Constants](FEATURES.md#constants) | |
| [Destructuring assignment](FEATURES.md#destructuring-assignment) | |
| [Array comprehension](FEATURES.md#array-comprehension) | |
| [Generators](FEATURES.md#generators) | |
## Installation
$ npm install -g 6to5
## Usage
### CLI
Compile the file `script.js` and output it to `script-compiled.js`.
$ 6to5 script.js -o script-compiled.js
Compile the entire `src` directory and output it to the `lib` directory.
$ 6to5 src -d lib
Compile the file `script.js` and output it to stdout.
$ 6to5 script.js
### Browserify
$ browserify script.js -t 6to5/browserify --outfile bundle.js
### Node
```javascript
var to5 = require("6to5");
to5.transform("code();");
to5.transformFileSync("script.js");
to5.transformFile("script.js", function (err, data) {
});
```
##### Options
```javascript
to5.transform("code();", {
// List of transformers to EXCLUDE
// This is a camelised version of the name found in `features`
// eg. "Arrow functions" is "arrowFunctions"
blacklist: [],
// List of transformers to ONLY use.
// See `blacklist` for naming scheme.
whitelist: [],
// Append source map and comment to bottom of returned output.
sourceMap: false,
// Filename for use in errors etc.
filename: "unknown",
// Format options
// See https://github.com/Constellation/escodegen/wiki/API for options.
format: {}
});
```
#### Require hook
All subsequent files required by node will be transformed into ES5 compatible
code.
```javascript
require("6to5/register");
```
#### Connect Middleware
```javascript
var to5 = require("6to5");
app.use(to5.middleware({
options: {
// options to use when transforming files
},
src: "assets",
dest: "cache"
}));
app.use(connect.static("cache"));
```
#### Browserify
```javascript
var to5 = require("6to5");
browserify()
.transform(to5.browserify)
.require("script.js", { entry: true })
.bundle({ debug: true })
.pipe(fs.createWriteStream("bundle.js"));
```
## Comparison to Traceur
### Performance