Duplicates a group of form fields and makes their attributes unique (great for nested_attributes in Rails)

gistfile1.js

jQuery.fn.make_attr_unique = function(attr) {
  var value = $(this).attr(attr);
  if (value !== undefined) {
    var value_pieces = value.split(/[0-9]+/);
    if (value_pieces.length > 1) {
      $(this).attr(attr, value_pieces[0] + Number(new Date()) + value_pieces[1]); 
    }
  }
};
  
jQuery.fn.clone_fields_unique = function() {
  var clone = $(this).clone(false);

  clone.find('textarea,input,label').each(function() {
    $(this).make_attr_unique('id'); 
    $(this).make_attr_unique('name'); 
    $(this).make_attr_unique('for'); 
  });
  
  return clone;
};

$('.snippet').clone_fields_unique().appendTo('.snippets');