# babel-generator

> Turns an AST into code.

Latest version **6.26.1** (published 2018-02-03) · MIT license · 0 weekly downloads

## Install

```sh
npm install babel-generator
pnpm add babel-generator
yarn add babel-generator
bun add babel-generator
```

## Health

**Score 38/100 (D)** — status: abandoned.

Positive: has types package; no vulnerabilities; high maintenance score; popular repo.

Warnings: low downloads; no esm support.

Negative: abandoned.

## Facts

| | |
|---|---|
| Version | 6.26.1 |
| Published | 2018-02-03 |
| First published | 2015-10-29 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | separate (@types/babel-generator) |
| Module format | CommonJS |
| Dependencies | 8 |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 44000 |
| Author | Sebastian McKenzie |
| Maintainers | existentialism, thejameskyle, sebmck, danez, hzoo, loganfsmyth |

## Links

- npm: https://www.npmjs.com/package/babel-generator
- Repository: https://github.com/babel/babel/tree/master/packages/babel-generator
- Homepage: https://babeljs.io/
- npm.io page: https://npm.io/package/babel-generator

## Dependencies (8)

- [jsesc](https://npm.io/package/jsesc.md) ^1.3.0
- [lodash](https://npm.io/package/lodash.md) ^4.17.4
- [source-map](https://npm.io/package/source-map.md) ^0.5.7
- [trim-right](https://npm.io/package/trim-right.md) ^1.0.1
- [babel-types](https://npm.io/package/babel-types.md) ^6.26.0
- [babel-runtime](https://npm.io/package/babel-runtime.md) ^6.26.0
- [detect-indent](https://npm.io/package/detect-indent.md) ^4.0.0
- [babel-messages](https://npm.io/package/babel-messages.md) ^6.23.0

## Recent versions

- 6.26.1 (latest) — 2018-02-03
- 7.0.0-beta.3 (next) — 2017-10-15
- 7.0.0-beta.2 — 2017-09-26
- 7.0.0-beta.1 — 2017-09-19
- 7.0.0-beta.0 — 2017-09-12
- 7.0.0-alpha.20 — 2017-08-30
- 6.26.0 — 2017-08-16
- 7.0.0-alpha.19 — 2017-08-07
- 7.0.0-alpha.18 — 2017-08-03
- 7.0.0-alpha.17 — 2017-07-26
- 7.0.0-alpha.16 — 2017-07-25
- 7.0.0-alpha.15 — 2017-07-12
- 7.0.0-alpha.14 — 2017-07-12
- 6.25.0 — 2017-06-08
- 7.0.0-alpha.12 — 2017-05-31
- … 79 more at https://npm.io/package/babel-generator/versions

## README

# babel-generator

> Turns an AST into code.

## Install

```sh
npm install --save-dev babel-generator
```

## Usage

```js
import {parse} from 'babylon';
import generate from 'babel-generator';

const code = 'class Example {}';
const ast = parse(code);

const output = generate(ast, { /* options */ }, code);
```

## Options

Options for formatting output:

name                   | type     | default         | description
-----------------------|----------|-----------------|--------------------------------------------------------------------------
auxiliaryCommentBefore | string   |                 | Optional string to add as a block comment at the start of the output file
auxiliaryCommentAfter  | string   |                 | Optional string to add as a block comment at the end of the output file
shouldPrintComment     | function | `opts.comments` | Function that takes a comment (as a string) and returns `true` if the comment should be included in the output.  By default, comments are included if `opts.comments` is `true` or if `opts.minifed` is `false` and the comment contains `@preserve` or `@license`
retainLines            | boolean  | `false`         | Attempt to use the same line numbers in the output code as in the source code (helps preserve stack traces)
retainFunctionParens   | boolean  | `false`         | Retain parens around function expressions (could be used to change engine parsing behavior)
comments               | boolean  | `true`          | Should comments be included in output
compact                | boolean or `'auto'` | `opts.minified` | Set to `true` to avoid adding whitespace for formatting
minified               | boolean  | `false`         | Should the output be minified
concise                | boolean  | `false`         | Set to `true` to reduce whitespace (but not as much as `opts.compact`)
quotes                 | `'single'` or `'double'` | autodetect based on `ast.tokens` | The type of quote to use in the output
filename               | string   |                 | Used in warning messages
flowCommaSeparator     | boolean  | `false`         | Set to `true` to use commas instead of semicolons as Flow property separators
jsonCompatibleStrings  | boolean  | `false`         | Set to true to run `jsesc` with "json": true to print "\u00A9" vs. "©";

Options for source maps:

name                   | type     | default         | description
-----------------------|----------|-----------------|--------------------------------------------------------------------------
sourceMaps             | boolean  | `false`         | Enable generating source maps
sourceMapTarget        | string   |                 | The filename of the generated code that the source map will be associated with
sourceRoot             | string   |                 | A root for all relative URLs in the source map
sourceFileName         | string   |                 | The filename for the source code (i.e. the code in the `code` argument).  This will only be used if `code` is a string.

## AST from Multiple Sources

In most cases, Babel does a 1:1 transformation of input-file to output-file.  However,
you may be dealing with AST constructed from multiple sources - JS files, templates, etc.
If this is the case, and you want the sourcemaps to reflect the correct sources, you'll need
to pass an object to `generate` as the `code` parameter.  Keys
should be the source filenames, and values should be the source content.

Here's an example of what that might look like:

```js
import {parse} from 'babylon';
import generate from 'babel-generator';

const a = 'var a = 1;';
const b = 'var b = 2;';
const astA = parse(a, { sourceFilename: 'a.js' });
const astB = parse(b, { sourceFilename: 'b.js' });
const ast = {
  type: 'Program',
  body: [].concat(astA.program.body, astB.program.body)
};

const { code, map } = generate(ast, { sourceMaps: true }, {
  'a.js': a,
  'b.js': b
});

// Sourcemap will point to both a.js and b.js where appropriate.
```

---
_Source: https://npm.io/package/babel-generator · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._