Lodash Internal Object Types

Common errors

• TypeError: (0, _lodash_objecttypes.default) is not a function

  cause Attempting to use ES module `import objectTypes from 'lodash._objecttypes';` or `import { default as objectTypes } from 'lodash._objecttypes';` when the package is CommonJS and does not have a default export.
  fix Use CommonJS `require` syntax: `const objectTypes = require('lodash._objecttypes');`

• Error: Cannot find module 'lodash._objecttypes'

  cause Trying to import this package in a modern Lodash setup, where it is no longer published or included, or if the package manager cannot resolve the ancient version.
  fix This package is abandoned and not part of modern Lodash. Do not use it. Instead, use the public API of the main `lodash` package (e.g., `_.isObjectLike`) or `lodash-es` if you need modular ES imports.

• TypeError: require(...) is not a function

  cause After `const objectTypes = require('lodash._objecttypes');`, attempting to call `objectTypes()` as a function. The `objectTypes` variable is an object, not a function.
  fix Access properties of `objectTypes` directly, e.g., `objectTypes[typeof myVar]`. Do not call it as a function.

Warnings

• breaking This package is an internal utility from Lodash v2.x (released 2013). Its structure, content, and very existence are not stable and are subject to change or removal without notice in any modern Lodash version (v3, v4, or later). Directly depending on it will almost certainly lead to breakage.
  Fix: Do not use internal Lodash packages. Rely solely on the public API of the main `lodash` package or its officially modularized versions (e.g., `lodash-es`).
• deprecated The entire pattern of exposing granular internal Lodash components as separate npm packages (like `lodash._objecttypes`) has been deprecated. Modern Lodash (v4.x) integrates such utilities internally or provides ES module versions via `lodash-es` for tree-shaking.
  Fix: Migrate any direct usage to public Lodash API methods. If you are examining Lodash internals, refer to the source code of the main `lodash` repository for the relevant version.
• gotcha Lodash v2.4.1, which this package is tied to, is affected by numerous known security vulnerabilities (e.g., Prototype Pollution, Code Injection, Regular Expression Denial of Service) that have been patched in later versions of the main `lodash` library. Using any code derived from such an old version, even an internal utility, introduces significant security risks.
  Fix: Upgrade to the latest stable version of the main `lodash` package (currently 4.18.1 or higher) and leverage its public API. Do not use unmaintained internal modules.
• gotcha This package is strictly CommonJS (`require()`). It does not provide ES module exports (`import`). Attempting to `import` it will result in syntax errors or runtime issues in modern JavaScript environments unless transpiled.
  Fix: If you absolutely must inspect or use this internal module (which is strongly discouraged), use `const objectTypes = require('lodash._objecttypes');`.

Install

• npm install lodash._objecttypes npm
• yarn add lodash._objecttypes yarn
• pnpm add lodash._objecttypes pnpm

Imports

• objectTypes
  wrong:

  import objectTypes from 'lodash._objecttypes';

  correct:

  const objectTypes = require('lodash._objecttypes');

  This package is CommonJS-only from Lodash v2.x. Attempting to use ES module `import` syntax will result in errors as it does not export a default or named exports in that format.
• objectTypes
  wrong:

  const objectTypes = require('lodash._objecttypes')();

  correct:

  const objectTypes = require('lodash._objecttypes');
  // Then use objectTypes for internal checks, e.g., objectTypes[typeof value]

  The `objectTypes` export is an object, not a function. Calling it as a function will result in a TypeError.
• type checks
  wrong:

  const internalTypes = require('lodash._objecttypes');
  if (internalTypes[typeof myVar]) { /* ... */ }

  correct:

  // Prefer using official Lodash methods like _.isObject, _.isString, etc., from the main 'lodash' package.
  const _ = require('lodash');
  _.isObject({});

  This package exports internal details. For type checking, always use the robust, public API functions provided by the main `lodash` package, which are properly maintained and handle edge cases.

Quickstart

Demonstrates the CommonJS import and the structure of the `objectTypes` object, illustrating its internal purpose in Lodash v2.

const objectTypes = require('lodash._objecttypes');

// In Lodash v2, 'objectTypes' was used internally for quick type checks.
// It typically mapped JavaScript's `typeof` results to booleans.
// For example, to check if a value was an 'object' or 'function'.

console.log('--- lodash._objecttypes example ---');
console.log('Object types map:', objectTypes);

// Example of how it might have been used internally (simplified):
function isObjectLike(value) {
  return objectTypes[typeof value] === true;
}

console.log(`isObjectLike(null): ${isObjectLike(null)}`); // null is 'object' via typeof
console.log(`isObjectLike({}): ${isObjectLike({})}`);
console.log(`isObjectLike([]): ${isObjectLike([])}`);
console.log(`isObjectLike(() => {}): ${isObjectLike(() => {})}`);
console.log(`isObjectLike(123): ${isObjectLike(123)}`);

// Note: For actual Lodash usage, always use the main 'lodash' package:
// const _ = require('lodash');
// console.log(`_.isObjectLike({}): ${_.isObjectLike({})}`);