SO fiddle

Test Fiddle mainly for SO Questions

by Nick Craver

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/overcast/jquery-ui.css">
<div>Test</div>
<div>Test</div>
<div>Test</div>

JavaScript

jQuery.fn.require = function(num, num2) {
  if(this.length < num) $.error("At least " + num + " elements are required");
  if(num2 && this.length > num2) $.error("Between " + num + " and " + num2 + " elements required");
};

$("div").require(1, 2);