bare-module-lexer

Heuristic lexer for detecting imports and exports in JavaScript modules. It trades off correctness for performance, aiming to reliably support the most common import and export patterns with as little overhead as possible.

Usage

``js
const lex = require('bare-module-lexer')

lex(
const foo = require('./foo.js')
exports.bar = 42
)

// {
// imports: [
// { specifier: './foo.js', type: REQUIRE, names: [], position: [ 15, 24, 32 ] }
// ],
// exports: [
// { name: 'bar', position: [ 37, 45, 48 ] }
// ]
// }
`

API

#### const { imports, exports } = lex(source[, encoding][, options])

imports is an array of objects with the following shape:

`js
imports = {
specifier: 'string',
type: number,
names: ['string'],
position: [
number, // Import start
number, // Specifier start
number // Specifier end
]
}
`

exports is an array of objects with the following shape:

`js
exports = {
name: 'string',
position: [
number, // Export start
number, // Name start
number // Name end
]
}
`

Options are reserved.

#### lex.constants

| Constant | Description |
| :--------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| REQUIRE | CommonJS require(). |
| IMPORT | ES module import. |
| DYNAMIC | ES module import() if IMPORT is set. |
| ADDON | CommonJS require.addon() if REQUIRE is set, or ES module import.meta.addon() if IMPORT is set. |
| ASSET | CommonJS require.asset() if REQUIRE is set, or ES module import.meta.asset() if IMPORT is set. |
| RESOLVE | CommonJS require.resolve() or require.addon.resolve() if REQUIRE and optionally ADDON are set, or ES module import.meta.resolve() or import.meta.addon.resolve() if IMPORT and optionally ADDON are set. |
| REEXPORT | Re-export of a CommonJS require() if REQUIRE is set, or ES module export from if IMPORT` is set. |

License

Apache-2.0