amdefine: AMD Define for Node.js

Common errors

• ReferenceError: define is not defined

  cause The `define` function provided by `amdefine` was not correctly loaded or made available in the module's scope.
  fix Ensure the conditional snippet `if (typeof define !== 'function') { var define = require('amdefine')(module) }` is present and correctly placed at the very top of your AMD module file, or that `require('amdefine/intercept')` is executed early in your application's entry point.

• ReferenceError: require is not defined

  cause You are attempting to use `require()` directly inside an AMD `define` factory function without it being explicitly provided.
  fix Use the CommonJS-wrapped AMD format by declaring `define(function (require) { ... })` to get `require` as an argument, or include 'require' in your dependency array: `define(['require', 'dependency'], function(require, dependency) { ... })`.

Warnings

• gotcha Using `amdefine/intercept` modifies Node.js's global module loading behavior by overriding `Module._extensions['.js']`. This can lead to unexpected side effects or conflicts with other modules that modify the same extension hook. It is explicitly discouraged for reusable library code.
  Fix: For library code or scenarios requiring more control, avoid `amdefine/intercept`. Instead, use the conditional `if (typeof define !== 'function') { var define = require('amdefine')(module) }` snippet at the top of each individual AMD module.
• gotcha The specific structure of the conditional `define` snippet (`if (typeof define !== 'function') { var define = require('amdefine')(module) }`) is essential for compatibility with the RequireJS optimizer. Any significant deviation (e.g., adding extra statements within the `if` block) may prevent the optimizer from correctly stripping out the `amdefine` code for browser builds.
  Fix: Maintain the exact basic structure of the conditional `define` snippet to ensure proper optimization and code stripping by RequireJS.
• deprecated The AMD module format, while foundational, has largely been superseded by ES Modules (ESM) and CommonJS (CJS) for modern JavaScript development, especially in Node.js. `amdefine` itself has not been updated in many years, reflecting the declining relevance of AMD in the Node.js ecosystem.
  Fix: For new projects, consider using ES Modules or CommonJS for module definition. `amdefine` is best suited for maintaining or integrating existing AMD-based codebases within Node.js.

Install

• npm install amdefine npm
• yarn add amdefine yarn
• pnpm add amdefine pnpm

Imports

• define
  wrong:

  import { define } from 'amdefine'

  correct:

  if (typeof define !== 'function') { var define = require('amdefine')(module) }

  This exact conditional snippet must be placed at the top of each AMD module to ensure the `define` function is available when running in Node.js without a full AMD loader. Its precise structure is also critical for compatibility with the RequireJS optimizer's stripping behavior.
• amdefine/intercept
  wrong:

  import 'amdefine/intercept'

  correct:

  require('amdefine/intercept')

  This module globally applies the `define` shim by overriding Node.js's `Module._extensions['.js']` handler. It should only be used in top-level Node.js *applications* (e.g., `index.js`, `server.js`), not within reusable libraries, due to its global side effects.
• require (inside define)
  wrong:

  define(['dependency'], function () { var dep = require('dependency'); });

  correct:

  define(function (require) { var dep = require('dependency'); });

  When using the CommonJS-wrapped AMD style, `require` is passed as an argument to the factory function. If using the array-based dependency declaration, `require` must be explicitly listed in the dependency array (e.g., `define(['require', 'dependency'], function(require, dependency) { ... })`) to be available.

Quickstart

Demonstrates defining and consuming AMD modules using `amdefine` in a Node.js application, including the conditional `define` snippet and inter-module dependencies.

// --- package.json (excerpt) ---
// {
//   "dependencies": {
//     "amdefine": ">=0.1.0"
//   }
// }

// --- my-amd-module.js ---
if (typeof define !== 'function') {
  var define = require('amdefine')(module);
}

define(['./my-other-module'], function (myOtherModule) {
  'use strict';
  console.log('Inside my-amd-module.js');
  
  function greet(name) {
    return myOtherModule.sayHello(name) + ' from amdefine module.';
  }

  return {
    greet: greet,
  };
});

// --- my-other-module.js ---
if (typeof define !== 'function') {
  var define = require('amdefine')(module);
}

define(function () {
  'use strict';
  console.log('Inside my-other-module.js');

  function sayHello(name) {
    return 'Hello, ' + name;
  }

  return {
    sayHello: sayHello,
  };
});

// --- app.js (main entry point) ---
// Ensure 'npm install' has been run to get amdefine
const myAmdModule = require('./my-amd-module');

console.log('Running app.js');
console.log(myAmdModule.greet('World'));

// Expected console output:
// Inside my-other-module.js
// Inside my-amd-module.js
// Running app.js
// Hello, World from amdefine module.