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
babel-plugin-syntax-import-assertions
This Babel plugin allows Babel to parse import assertions. It is similar to acorn-import-assertions in that it extends the JavaScript parser to understand the import assertions syntax, but it is designed to work as part of the Babel ecosystem.
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.