acorn-import-assertions

What is acorn-import-assertions?

The acorn-import-assertions package is a plugin for the Acorn JavaScript parser. It adds support for parsing import assertions, which are a stage 3 proposal for ECMAScript that allows developers to make assertions about the type of module they are importing. This is particularly useful for distinguishing between different types of modules, such as JSON modules, CSS modules, or other non-JavaScript content.

What are acorn-import-assertions's main functionalities?

Parsing import assertions

This feature allows the parsing of import statements with assertions. The code sample demonstrates how to extend the Acorn parser with the importAssertions plugin and parse a piece of code that includes an import statement with an assertion.

import assert from 'assert';
import { Parser } from 'acorn';
import importAssertions from 'acorn-import-assertions';

const code = "import json from './data.json' assert { type: 'json' };";
const ast = Parser.extend(importAssertions).parse(code, { sourceType: 'module' });
assert(ast.body[0].assertions[0].value.value === 'json');

Other packages similar to acorn-import-assertions

es-module-lexer

es-module-lexer is a fast lexer for ES module syntax, including import assertions. While acorn-import-assertions is a plugin for the Acorn parser, es-module-lexer is a standalone lexer that can be used for tooling that needs to understand ES module syntax quickly and efficiently.

README

Support for import assertions in acorn

Usage

This module provides a plugin that can be used to extend the Acorn Parser class:

const {Parser} = require('acorn');
const {importAssertions} = require('acorn-import-assertions');
Parser.extend(importAssertions).parse('...');

License

This plugin is released under an MIT License.