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# Lodash isNull
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The lodash isNull function is a utility that checks if a given value is strictly equal to `null`. This function is part of the lodash Lang category and provides a reliable way to test for null values in JavaScript applications.
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## Package Information
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- **Package Name**: lodash
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- **Package Type**: npm
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- **Language**: JavaScript
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- **Installation**: `npm install lodash`
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- **Version**: 3.0.0
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## Core Imports
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ESM/ES6 Modules:
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```javascript
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import _ from "lodash";
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```
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CommonJS/Node.js:
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```javascript
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const _ = require("lodash");
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```
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## Basic Usage
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```javascript
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import _ from "lodash";
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// Check for null value
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console.log(_.isNull(null));        // => true
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console.log(_.isNull(undefined));   // => false
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console.log(_.isNull(0));          // => false
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console.log(_.isNull(""));         // => false
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console.log(_.isNull(false));      // => false
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```
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## Capabilities
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### Null Value Detection
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Checks if a value is `null` using strict equality comparison.
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```javascript { .api }
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/**
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 * Checks if `value` is `null`.
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 *
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 * @static
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 * @memberOf _
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 * @category Lang
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 * @param {*} value The value to check.
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 * @returns {boolean} Returns `true` if `value` is `null`, else `false`.
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 */
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function isNull(value);
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```
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**Usage Examples:**
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```javascript
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// Basic null checking
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_.isNull(null);
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// => true
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_.isNull(void 0);  // undefined
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// => false
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// Testing with various falsy values
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_.isNull(false);
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// => false
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_.isNull(0);
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// => false
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_.isNull("");
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// => false
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_.isNull(NaN);
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// => false
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// Testing with objects and arrays
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_.isNull({});
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// => false
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_.isNull([]);
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// => false
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// Testing with functions
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_.isNull(function() {});
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// => false
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```
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**Implementation Details:**
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- Uses strict equality (`===`) comparison with `null`
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- Returns `true` only for `null` values
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- Returns `false` for all other values including `undefined`, `0`, `false`, `""`, and `NaN`
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- Cross-realm compatible - works with null values from different JavaScript contexts
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- No dependencies on other lodash functions
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- Optimized for performance with single comparison operation
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**Common Use Cases:**
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- Form validation where null values need to be identified
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- API response processing where null indicates missing data
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- Data cleaning operations to identify null values in datasets
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- Conditional logic where null values require special handling
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- Type guards in TypeScript when used with type assertions
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**Error Handling:**
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This function does not throw any errors. It safely handles all JavaScript value types including:
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- Primitive values (string, number, boolean, symbol, bigint)
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- Object values (objects, arrays, functions, dates, etc.)
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- Special values (null, undefined, NaN)
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- Host objects (in browser environments)