babel-plugin-syntax-function-sent

babel-plugin-syntax-function-sent is a Babel syntax plugin that enables parsing of the function.sent meta property in JavaScript code. This is a pure syntax plugin that only extends Babel's parser capabilities without transforming code - it allows JavaScript generators to use function.sent syntax during the compilation process.

Package Information

• Package Name: babel-plugin-syntax-function-sent
• Package Type: npm
• Language: JavaScript
• Installation: npm install babel-plugin-syntax-function-sent

Core Imports

Since this is a Babel plugin, it's not imported directly in your code. Instead, it's configured as part of your Babel setup:

// Via require (if needed programmatically)
const syntaxFunctionSent = require("babel-plugin-syntax-function-sent");

Basic Usage

The plugin is configured in your Babel setup to enable function.sent syntax parsing:

Via .babelrc (Recommended)

{
  "plugins": ["syntax-function-sent"]
}

Via CLI

$ babel --plugins syntax-function-sent script.js

Via Node API

require("babel-core").transform("code", {
  plugins: ["syntax-function-sent"]
});

What it enables

Once configured, you can use function.sent syntax in your JavaScript generators:

function* example() {
  const value = function.sent;
  // ... generator code
}

Architecture

This plugin follows the standard Babel plugin architecture:

• Plugin Factory: The main default export returns a Babel plugin object
• Parser Extension: Uses the manipulateOptions hook to add parser capability
• Syntax Only: No code transformation - purely enables parsing
• Zero Dependencies: Lightweight with no runtime dependencies

Capabilities

Plugin Factory Function

The main entry point that creates a Babel plugin instance.

/**
 * Main plugin factory function that returns a Babel plugin object
 * @returns {BabelPlugin} Plugin object with manipulateOptions method
 */
export default function(): BabelPlugin;

interface BabelPlugin {
  manipulateOptions(opts: any, parserOpts: ParserOptions): void;
}

interface ParserOptions {
  plugins: string[];
}

The plugin factory function:

• Takes no parameters
• Returns a Babel plugin object
• The returned object contains a manipulateOptions method
• The manipulateOptions method adds "functionSent" to the parser's plugin array

Usage Example:

// Direct usage (typically not needed)
const plugin = require("babel-plugin-syntax-function-sent");
const pluginInstance = plugin();

// The plugin is normally used through Babel configuration
// It enables parsing of function.sent in generator functions

manipulateOptions Method

The Babel plugin hook that modifies parser options to enable function.sent syntax.

/**
 * Babel plugin hook that modifies parser options to enable function.sent syntax
 * @param {any} opts - Babel options object (unused by this plugin)
 * @param {ParserOptions} parserOpts - Parser options object that gets modified
 * @returns {void}
 */
manipulateOptions(opts: any, parserOpts: ParserOptions): void;

This method:

• Receives Babel's options and parser options
• Adds "functionSent" to the parserOpts.plugins array
• Enables the parser to recognize function.sent syntax
• Does not transform or modify the code itself

Types

/**
 * Babel plugin object interface
 */
interface BabelPlugin {
  manipulateOptions(opts: any, parserOpts: ParserOptions): void;
}

/**
 * Parser options interface
 */
interface ParserOptions {
  plugins: string[];
}

Error Handling

This plugin operates at the parser level and does not throw runtime errors. Parse errors would be handled by Babel's parser if invalid function.sent syntax is encountered.

Notes

• This is a syntax-only plugin - it does not transform code
• Enables parsing of the function.sent meta property in JavaScript generators
• Must be configured in Babel setup, not imported in application code
• Zero runtime dependencies and minimal performance impact
• Compatible with all Babel configurations and build tools