[jQuery] Benefit of extending jQuery with a function vs. a JavaScript function?

[marty.mcgee]

Hello, Marty McGee here.  I was hoping to open a discussion about the
benefits of extending jQuery with your own custom functions versus
simply writing your functions in JavaScript and calling them without
extending jQuery first.  Please enlighten me and the rest of the
humble jQuery library addicts.  Thanks to all.

For example, this:

$(function(){
  $.function_name = function test() {
    alert('in function');
  }
});

Versus this:

$(function(){
  test();
});

function test() {
  alert('in function');
}

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