Why does jQuery have a function named once?

There’s no reason for the closure to maintain a reference to context once fn has been called. [*] Be aware, though, that other libraries, such as this Drupal extension to jQuery, may have a function named once () that does something quite different. @EgyCode - This is explained nicely in the MDN documentation on closures.
For More Information Please Refer:
https://stackoverflow.com/questions/12713564/function-in-javascript-that-can-be-called-only-once
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