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# Type Detect
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Type Detect is an improved typeof detection library for Node.js, Deno, and browsers. It provides more specific type detection than JavaScript's native `typeof` operator, normalizing behavior across different engines and offering detailed type information for objects, arrays, and modern ECMAScript types.
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## Package Information
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- **Package Name**: type-detect
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- **Package Type**: npm
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- **Language**: TypeScript
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- **Installation**: `npm install type-detect`
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## Core Imports
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```typescript
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import typeDetect from "type-detect";
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```
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For CommonJS:
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```javascript
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const typeDetect = require("type-detect");
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```
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For Deno:
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```typescript
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import typeDetect from "https://deno.land/x/type_detect@v4.1.0/index.ts";
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```
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For browsers (UMD):
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```html
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<script src="./node_modules/type-detect/type-detect.js"></script>
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<script>
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  var typeDetect = typeDetect; // Available globally
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</script>
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```
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## Basic Usage
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```typescript
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import typeDetect from "type-detect";
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// Basic types
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console.log(typeDetect("hello"));        // "string"
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console.log(typeDetect(42));            // "number"
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console.log(typeDetect(true));          // "boolean"
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console.log(typeDetect(null));          // "null"
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console.log(typeDetect(undefined));     // "undefined"
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// Objects and arrays
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console.log(typeDetect([]));            // "Array"
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console.log(typeDetect({}));            // "Object"
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console.log(typeDetect(/regex/));       // "RegExp"
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console.log(typeDetect(new Date()));    // "Date"
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// ES6+ types
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console.log(typeDetect(new Map()));     // "Map"
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console.log(typeDetect(new Set()));     // "Set"
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console.log(typeDetect(Symbol()));      // "symbol"
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console.log(typeDetect(Promise.resolve())); // "Promise"
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// Typed arrays
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console.log(typeDetect(new Int32Array())); // "Int32Array"
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console.log(typeDetect(new Float64Array())); // "Float64Array"
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// Browser DOM elements (when available)
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if (typeof document !== 'undefined') {
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  console.log(typeDetect(document)); // "Document"
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  console.log(typeDetect(document.createElement('div'))); // "HTMLDivElement"
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}
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```
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## Architecture
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Type Detect uses a carefully optimized algorithm that:
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- **Performance First**: Specialized checks that are 20-30x faster than Object.prototype.toString for certain values
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- **Cross-Platform**: Normalizes behavior across Node.js, Deno, and different browser engines
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- **Modern Types**: Full support for ES6+ types, iterators, and typed arrays
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- **Browser DOM**: Special handling for DOM elements and browser-specific objects
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- **Zero Dependencies**: No runtime dependencies for minimal footprint
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## Capabilities
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### Enhanced Type Detection
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The core type detection functionality that serves as a drop-in replacement for JavaScript's `typeof` operator with enhanced specificity and cross-platform consistency.
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```typescript { .api }
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function typeDetect(obj: unknown): string;
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```
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**Parameters:**
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- `obj` (`unknown`): The value to analyze for type detection
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**Returns:**
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- `string`: A string representing the detected type
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**Supported Return Types:**
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#### Primitive Types
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- `"string"` - String literals
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- `"number"` - Number literals (including Infinity, NaN)
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- `"boolean"` - Boolean literals  
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- `"undefined"` - Undefined values
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- `"function"` - Function objects
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- `"symbol"` - Symbol values
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#### Object Types
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- `"null"` - Null values
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- `"Array"` - Arrays and array-like objects
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- `"Object"` - Plain objects and custom objects
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- `"RegExp"` - Regular expressions
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- `"Date"` - Date objects
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- `"Error"` - Error objects (Error, TypeError, RangeError, etc.)
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#### Wrapped Primitive Types
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- `"String"` - String objects (new String())
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- `"Number"` - Number objects (new Number())
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- `"Boolean"` - Boolean objects (new Boolean())
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#### ES6+ Types
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- `"Map"` - Map objects
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- `"Set"` - Set objects
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- `"WeakMap"` - WeakMap objects
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- `"WeakSet"` - WeakSet objects
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- `"Promise"` - Promise objects
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- `"DataView"` - DataView objects
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#### Iterator Types
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- `"Map Iterator"` - Map iterator objects
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- `"Set Iterator"` - Set iterator objects
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- `"Array Iterator"` - Array iterator objects
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- `"String Iterator"` - String iterator objects
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#### Typed Array Types
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- `"Int8Array"`, `"Uint8Array"`, `"Uint8ClampedArray"`
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- `"Int16Array"`, `"Uint16Array"`
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- `"Int32Array"`, `"Uint32Array"`
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- `"Float32Array"`, `"Float64Array"`
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- `"ArrayBuffer"`
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#### Browser-Specific Types
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- `"global"` - Global object (window in browsers)
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- `"Location"` - window.location
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- `"Document"` - window.document
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- `"DOMParser"` - DOMParser objects
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- `"History"` - window.history
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- `"Event"` - DOM events
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- `"HashChangeEvent"` - Hash change events
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- `"Attr"` - DOM attribute objects
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#### Navigator Object Types
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- `"Navigator"` - window.navigator
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- `"Geolocation"` - navigator.geolocation
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- `"NetworkInformation"` - navigator.connection
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- `"MediaDevices"` - navigator.mediaDevices
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- `"MimeTypeArray"` - navigator.mimeTypes
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- `"NFC"` - navigator.nfc
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- `"Permissions"` - navigator.permissions
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- `"PluginArray"` - navigator.plugins
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- `"Plugin"` - Individual plugin objects
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- `"Presentation"` - navigator.presentation
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- `"ServiceWorkerContainer"` - navigator.serviceworker
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- `"ServicePortCollection"` - navigator.services
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- `"StorageManager"` - navigator.storage
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- `"StorageQuota"` - navigator.storageQuota
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- `"USB"` - navigator.usb
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#### HTML Element Types
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- `"HTMLElement"` - Generic HTML elements
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- `"HTMLAreaElement"` - `<area>` elements
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- `"HTMLBRElement"` - `<br>` elements
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- `"HTMLBaseElement"` - `<base>` elements
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- `"HTMLBodyElement"` - `<body>` elements
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- `"HTMLButtonElement"` - `<button>` elements
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- `"HTMLCanvasElement"` - `<canvas>` elements
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- `"HTMLDListElement"` - `<dl>` elements
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- `"HTMLDataListElement"` - `<datalist>` elements
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- `"HTMLDivElement"` - `<div>` elements
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- `"HTMLFieldSetElement"` - `<fieldset>` elements
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- `"HTMLFormElement"` - `<form>` elements
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- `"HTMLFrameSetElement"` - `<frameset>` elements
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- `"HTMLHRElement"` - `<hr>` elements
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- `"HTMLHeadElement"` - `<head>` elements
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- `"HTMLHeadingElement"` - `<h1>` through `<h6>` elements
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- `"HTMLHtmlElement"` - `<html>` elements
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- `"HTMLIFrameElement"` - `<iframe>` elements
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- `"HTMLImageElement"` - `<img>` elements
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- `"HTMLInputElement"` - `<input>` elements
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- `"HTMLLIElement"` - `<li>` elements
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- `"HTMLLabelElement"` - `<label>` elements
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- `"HTMLLegendElement"` - `<legend>` elements
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- `"HTMLLinkElement"` - `<link>` elements
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- `"HTMLMapElement"` - `<map>` elements
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- `"HTMLMetaElement"` - `<meta>` elements
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- `"HTMLMeterElement"` - `<meter>` elements
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- `"HTMLModElement"` - `<del>` and `<ins>` elements
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- `"HTMLOListElement"` - `<ol>` elements
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- `"HTMLOptGroupElement"` - `<optgroup>` elements
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- `"HTMLOptionElement"` - `<option>` elements
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- `"HTMLOutputElement"` - `<output>` elements
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- `"HTMLParagraphElement"` - `<p>` elements
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- `"HTMLParamElement"` - `<param>` elements
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- `"HTMLPreElement"` - `<pre>` elements
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- `"HTMLProgressElement"` - `<progress>` elements
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- `"HTMLQuoteElement"` - `<blockquote>` and `<q>` elements
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- `"HTMLScriptElement"` - `<script>` elements
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- `"HTMLSelectElement"` - `<select>` elements
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- `"HTMLSpanElement"` - `<span>` elements
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- `"HTMLStyleElement"` - `<style>` elements
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- `"HTMLTableCaptionElement"` - `<caption>` elements
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- `"HTMLTableDataCellElement"` - `<td>` elements
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- `"HTMLTableHeaderCellElement"` - `<th>` elements
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- `"HTMLTableColElement"` - `<col>` and `<colgroup>` elements
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- `"HTMLTableElement"` - `<table>` elements
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- `"HTMLTableRowElement"` - `<tr>` elements
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- `"HTMLTableSectionElement"` - `<thead>`, `<tbody>`, `<tfoot>` elements
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- `"HTMLTextAreaElement"` - `<textarea>` elements
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- `"HTMLTitleElement"` - `<title>` elements
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- `"HTMLUListElement"` - `<ul>` elements
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- `"HTMLUnknownElement"` - Unknown/custom HTML elements
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#### Function-Specific Types
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- `"Arguments"` - Arguments objects
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- `"Generator"` - Generator objects from generator functions
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#### Node.js-Specific Types
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- `"process"` - Node.js process object
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#### Custom Types
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- Support for custom types via `Symbol.toStringTag`
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**Usage Examples:**
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```typescript
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import typeDetect from "type-detect";
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// Enhanced object detection
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const values = [
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  [],
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  new Array(),
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  /regex/gi,
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  new RegExp('pattern'),
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  new Date(),
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  new Map(),
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  new Set(),
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  new WeakMap(),
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  new WeakSet(),
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  Symbol('test'),
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  Promise.resolve(),
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  new Int32Array(10),
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  new Float64Array(5),
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  new ArrayBuffer(16),
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  new DataView(new ArrayBuffer(16))
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];
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values.forEach(value => {
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  console.log(`${value} -> ${typeDetect(value)}`);
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});
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// Custom types with Symbol.toStringTag
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const customObject = {};
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customObject[Symbol.toStringTag] = 'CustomType';
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console.log(typeDetect(customObject)); // "CustomType"
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// Arguments object detection
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function testArgs() {
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  console.log(typeDetect(arguments)); // "Arguments"
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}
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testArgs(1, 2, 3);
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// Error types
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console.log(typeDetect(new Error())); // "Error"
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console.log(typeDetect(new TypeError())); // "Error"
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console.log(typeDetect(new RangeError())); // "Error"
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// Wrapped primitive types
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console.log(typeDetect(new Boolean(true))); // "Boolean"
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// Generator functions (when supported)
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function* generatorFunction() { yield 1; }
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const generator = generatorFunction();
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console.log(typeDetect(generator)); // "Generator"
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// Node.js specific types (when available)
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if (typeof process !== 'undefined') {
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  console.log(typeDetect(process)); // "process"
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}
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// Browser DOM elements (when available)
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if (typeof window !== 'undefined') {
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  console.log(typeDetect(window.location)); // "Location"
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  console.log(typeDetect(window.document)); // "Document"
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  const blockquote = document.createElement('blockquote');
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  console.log(typeDetect(blockquote)); // "HTMLQuoteElement"
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  const td = document.createElement('td');
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  console.log(typeDetect(td)); // "HTMLTableDataCellElement"
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}
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```
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**Performance Characteristics:**
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- Optimized fast paths for primitive types
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- 20-30x faster than Object.prototype.toString for certain values
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- Minimal memory allocation
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- Consistent performance across different JavaScript engines
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**Cross-Platform Behavior:**
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- Normalizes differences between Node.js, Deno, and browser environments
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- Handles engine-specific quirks and inconsistencies
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- Provides consistent results for modern ECMAScript features
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- Special handling for DOM elements and browser objects when available