Again, 'readyCallback' exists because it's a Bad Idea to run user code
during parsing (tree construction). Ready-time is not the same as
construct-time.
This is the Pinocchio problem:
http://lists.w3.org/Archives/Public/public-webapps/2013JanMar/0728.html
Scott
On Mon, Apr 15, 2013 at 7:45 AM, Rick Waldron <waldron.rick@gmail.com>wrote:
>
>
>
> On Mon, Apr 15, 2013 at 8:57 AM, Boris Zbarsky <bzbarsky@mit.edu> wrote:
>
>> On 4/14/13 5:35 PM, Rick Waldron wrote:
>>
>>> I have a better understanding of problem caused by these generated
>>> HTML*Element constructors: they aren't constructable.
>>>
>>
>> I'd like to understand what's meant here. I have a good understanding of
>> how these constructors work in Gecko+SpiderMonkey, but I'm not sure what
>> the lacking bit is, other than the fact that they have to create JS objects
>> that have special state associated with them, so can't work with an object
>> created by the [[Construct]] of a typical function.
>>
>> Is that what you're referring to, or something else?
>
>
> Sorry, I should've been more specific. What I meant was that:
>
> new HTMLButtonElement();
>
> Doesn't construct an HTMLButtonElement, it throws with an "illegal
> constructor" in Chrome and "HTMLButtonElement is not a constructor" in
> Firefox (I'm sure this is the same across other browsers)
>
> Which of course means that this is not possible even today:
>
> function Smile() {
> HTMLButtonElement.call(this);
> this.textContent = ":)";
> }
>
> Smile.prototype = Object.create(HTMLButtonElement.prototype);
>
>
> Since this doesn't work, the prototype method named "readyCallback" was
> invented as a bolt-on stand-in for the actual [[Construct]]
>
> Hopefully that clarifies?
>
> Rick
>
>
> PS. A bit of trivial... A long time ago some users requested that
> jQuery facilitate a custom constructor; to make this work, John put the
> actual constructor code in a prototype method called "init" and set that
> method's prototype to jQuery's own prototype. The thing called
> "readyCallback" is similar. For those that are interested, I created a gist
> with a minimal illustration here: https://gist.github.com/rwldrn/5388544
>
>
>
>
>
>>
>>
>> -Boris
>>
>
>