What does the $ Variable Represent in the Chrome Developer Console?
Native Function Referred by $ in Chrome
In the developer tools of Google Chrome, the $ variable holds a function accessible only through the console. Despite attempts to access it via various objects ($window, $document, $this), its purpose remains unknown.
Resolution
The behavior of $ in Chrome's console has evolved over time. Currently, it serves as an alias for document.querySelector(), enabling the selection of the first DOM element matching a CSS selector. Additionally, the console provides several other shortcuts, including:
- $$(selector): Returns an array of elements matching a CSS selector (equivalent to document.querySelectorAll())
- $_: Returns the value of the most recently evaluated expression
- $0 to $4: Provide historical references to recently inspected DOM elements or JavaScript heap objects
It's important to note that, while $ is an alias of document.querySelector(), $$ returns an array, and neither is strictly equal to its respective object method (e.g., $ !== document.querySelector()).
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