Calling a method on a jQuery collection

I was going through the Adding keyboard navigation and noticed that Remi replaced this code

1$(".coda-slider-wrapper ul a.current").parent().next().find("a").click();
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with this code

1var direction = "next";
2$(".coda-slider-wrapper ul a.current").parent()[direction]().find("a").click();
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I had never seen anything like that. In the above mentioned article, Remi used next and prev methods. However I wanted to know all the options I could pass since this feature is not very documented.

Snippet from jQuery source code

Here is code from jQuery that makes that above method work.

1jQuery.each(
2  {
3    parent: function (elem) {
4      return elem.parentNode;
5    },
6    parents: function (elem) {
7      return jQuery.dir(elem, "parentNode");
8    },
9    next: function (elem) {
10      return jQuery.nth(elem, 2, "nextSibling");
11    },
12    prev: function (elem) {
13      return jQuery.nth(elem, 2, "previousSibling");
14    },
15    nextAll: function (elem) {
16      return jQuery.dir(elem, "nextSibling");
17    },
18    prevAll: function (elem) {
19      return jQuery.dir(elem, "previousSibling");
20    },
21    siblings: function (elem) {
22      return jQuery.sibling(elem.parentNode.firstChild, elem);
23    },
24    children: function (elem) {
25      return jQuery.sibling(elem.firstChild);
26    },
27    contents: function (elem) {
28      return jQuery.nodeName(elem, "iframe")
29        ? elem.contentDocument || elem.contentWindow.document
30        : jQuery.makeArray(elem.childNodes);
31    },
32  },
33  function (name, fn) {
34    jQuery.fn[name] = function (selector) {
35      var ret = jQuery.map(this, fn);
36
37      if (selector && typeof selector == "string")
38        ret = jQuery.multiFilter(selector, ret);
39
40      return this.pushStack(jQuery.unique(ret), name, selector);
41    };
42  }
43);
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As you can see, a variety of selectors can be passed to jQueryCollection[].

If you want to give a try, any jQuery enabled site should perform all of the below mentioned code without any problem.

1var a = $("a:first");
2var log = console.log;
3
4log(a["parent"]());
5log(a["parents"]());
6log(a["next"]());
7log(a["prev"]());
8log(a["nextAll"]());
9log(a["prevAll"]());
10log(a["siblings"]());
11log(a["children"]());
12log(a["contents"]());
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