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# Lodash Keys
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Lodash Keys is a modularized version of lodash's `_.keys` functionality that creates an array of the own enumerable property names of an object. It provides a robust implementation with cross-browser compatibility and fallback support for environments without native Object.keys.
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## Package Information
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- **Package Name**: lodash.keys
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- **Package Type**: npm
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- **Language**: JavaScript
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- **Installation**: `npm install lodash.keys`
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## Core Imports
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```javascript
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var keys = require('lodash.keys');
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```
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For ES modules environments:
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```javascript
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import keys from 'lodash.keys';
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```
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## Basic Usage
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```javascript
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var keys = require('lodash.keys');
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// Get keys from a plain object
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var obj = { 'a': 1, 'b': 2, 'c': 3 };
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console.log(keys(obj)); // => ['a', 'b', 'c'] (iteration order is not guaranteed)
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// Works with constructor functions
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function Foo() {
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  this.a = 1;
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  this.b = 2;
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}
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Foo.prototype.c = 3;
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console.log(keys(new Foo)); // => ['a', 'b'] (excludes inherited properties)
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// Handles string objects
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console.log(keys('hi')); // => ['0', '1']
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// Returns empty array for null/undefined
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console.log(keys(null)); // => []
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console.log(keys(undefined)); // => []
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```
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## Capabilities
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### Object Keys Extraction
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Creates an array of the own enumerable property names of an object, excluding inherited properties.
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```javascript { .api }
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/**
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 * Creates an array of the own enumerable property names of object.
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 * Non-object values are coerced to objects.
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 * 
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 * @param {Object} object The object to query.
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 * @returns {Array} Returns the array of property names.
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 */
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function keys(object);
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```
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**Key Features:**
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- Uses native `Object.keys` when available and appropriate
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- Falls back to custom implementation for special cases (prototype objects, array-like objects)
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- Handles non-object values by coercing them to objects
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- Excludes inherited properties (own properties only)
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- Cross-browser compatible with fallbacks for older environments
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**Usage Examples:**
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```javascript
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var keys = require('lodash.keys');
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// Plain objects
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keys({ 'name': 'John', 'age': 30 }); // => ['name', 'age']
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// Arrays (returns string indices)
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keys(['a', 'b', 'c']); // => ['0', '1', '2']
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// Strings (returns character indices)
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keys('hello'); // => ['0', '1', '2', '3', '4']
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// Constructor instances (excludes prototype properties)
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function Person() {
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  this.name = 'John';
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  this.age = 30;
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}
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Person.prototype.species = 'human';
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keys(new Person()); // => ['name', 'age']
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// Array-like objects
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var arrayLike = { '0': 'a', '1': 'b', 'length': 2 };
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keys(arrayLike); // => ['0', '1', 'length']
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// Edge cases
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keys(null); // => []
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keys(undefined); // => []
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keys(42); // => [] (number coerced to Number object)
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keys(true); // => [] (boolean coerced to Boolean object)
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```
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## Browser Compatibility
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- Works in all modern browsers with native Object.keys support
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- Includes fallback implementation for older browsers (IE8 and below)
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- Handles various JavaScript engine quirks and edge cases
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- Optimized for performance using native methods when available
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## Dependencies
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This package depends on other modularized lodash utilities:
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- `lodash._getnative` (^3.0.0): For getting native method references
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- `lodash.isarguments` (^3.0.0): For detecting arguments objects
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- `lodash.isarray` (^3.0.0): For detecting arrays
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These dependencies are automatically installed and provide specialized functionality for robust object property enumeration across different JavaScript environments.