Implement Element.dataset

[termi]

I began to collect information on the possible IE8 shim.
A workaround can be found here http://eligrey.com/blog/post/html-5-dataset-support

[Raynos]

The problem with dataset is this.

el.dataset.foo = "bar";
assert(el.getAttribute("data-foo") === "bar");

This basically means we need to hook getAttribute, setAttribute and hasAttribute up so that it reads from the dataset.

[termi]

And what about for(var i in element.dataset){ } and Array.from(element.dataset)?

el.dataset.foo = "bar";

means that we need getter/setter, witch IE8 supported only for DOM Element :(

I mean we need more stronger solution.

[Raynos]

You don't need getter/setters on .foo you need an ES6 proxy

In theory this should work.

• dataset when got is pre populated with all the data- attributes
• You can set/get on the dataset and it will store it internally somewhere.
• Calls to getAttributes/setAttribute/attributes etc will reflect our internal dataset.
• We may want to periodically put all the changed attributes of the internal dataset on the actual DOM node through the real APIs

[Raynos]

Note things like this will never work. (not without proxies)

var e = document.createElement("div");
e.dataset.foo = "bar";
console.log(e.outerHTML);

[brettz9]

Doesn't address the issues mentioned here, but I have updated the original from Eli Grey with some improvements (including some changes taking advantage of his subsequent Xccessors shim): https://gist.github.com/4093766#file_html5_dataset.js