Question

Is there any jQuery function similar to closest() that will return elements outside of the parent chain, traversing sideways? For example, I want to call a function foo() on the div source that would return the div target. I know I could navigate using parent() and siblings(), but I need something generic that would go as many levels as needed, up, sideways and down?

var allsources = $('.source');

allsources.click(function()){
  $(this).closest('.target').hide();
});

<div class="row">
  <div>
     <div class="target" ></div>
  </div>
  <div>
    <div>
      <div class="source"></div>
    </div>
  </div>
</div>

<div class="row">
  <div>
     <div class="target" ></div>
  </div>
  <div>
    <div>
      <div class="source"></div>
    </div>
  </div>
</div>

EDIT:

My definition of closest: you have an element source. Try to find it down. If find more than one, return one that is less node hoops down/next/prev. If not found, go one level up, and try to find again. Repeat until no parent.

Answer 1

If, by closest, you mean “travel up as little as possible, then anywhere downwards”, then you can do

$("#source")
  .closest(":has(.target)")
  .find(".target:first")  //make sure we only select one element in case of a tie

In your case, it would be better to specify the common parent directly:

$(this)
  .closest(".row")
  .find(".target")        //there's no tie here, no need to arbitrate