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# lodash.size
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Gets the size of collections by returning the length for array-like values or the number of own enumerable properties for objects. This is a modularized build of lodash's `_.size` method, exported as a standalone Node.js module.
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## Package Information
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- **Package Name**: lodash.size
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- **Package Type**: npm
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- **Language**: JavaScript
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- **Installation**: `npm install lodash.size`
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## Core Imports
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```javascript
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var size = require('lodash.size');
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```
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For modern environments supporting ES modules:
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```javascript
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import size from 'lodash.size';
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```
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## Basic Usage
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```javascript
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var size = require('lodash.size');
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// Array size
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size([1, 2, 3]);
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// => 3
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// Object size (number of own enumerable properties)
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size({ 'a': 1, 'b': 2 });
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// => 2
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// String size
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size('pebbles');
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// => 7
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// Null/undefined handling
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size(null);
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// => 0
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size(undefined);
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// => 0
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// Empty values
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size([]);
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// => 0
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size({});
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// => 0
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size('');
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// => 0
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```
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## Capabilities
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### Size Calculation
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Gets the size of a collection by returning its length for array-like values or the number of own enumerable properties for objects.
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```javascript { .api }
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/**
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 * Gets the size of collection by returning its length for array-like
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 * values or the number of own enumerable properties for objects.
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 *
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 * @param {Array|Object|string} collection The collection to inspect.
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 * @returns {number} Returns the size of collection.
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 */
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function size(collection)
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```
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**Parameters:**
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- `collection` (Array|Object|string): The collection to inspect
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**Returns:**
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- (number): The size of collection
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**Behavior:**
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- For arrays and array-like objects (with numeric `length` property): returns the `length` value
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- For objects: returns the count of own enumerable properties (uses `lodash.keys` internally)
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- For strings: returns the string length
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- For `null` or `undefined`: returns `0`
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- For values with invalid length properties: falls back to counting object properties
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**Examples:**
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```javascript
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// Arrays
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size([1, 2, 3, 4, 5]);
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// => 5
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// Array-like objects
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size({ 0: 'a', 1: 'b', 2: 'c', length: 3 });
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// => 3
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// Plain objects
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size({ foo: 'bar', baz: 'qux' });
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// => 2
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// Strings
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size('hello world');
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// => 11
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// Edge cases
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size(null);          // => 0
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size(undefined);     // => 0
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size([]);           // => 0
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size({});           // => 0
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size('');           // => 0
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// Objects with length property that isn't valid
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size({ length: 'invalid', a: 1, b: 2 });
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// => 2 (counts properties, ignores invalid length)
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```