Re: Improving the DOM; rev 2

Do we really need "before" and "after"?

There's a clear risk that someone write a code like 
"myelement.firstChild.after(...)" and that the code throws a null-ref 
exception at runtime if (exceptionnaly) myelement was empty. I much prefer 
myelement.insertAfter and insertBefore, because they deal with such cases 
nicely. And because the name are more understandable.

Beside that small concern, I really like all the other additions.





-----Message d'origine----- 
From: Anne van Kesteren
Sent: Friday, November 18, 2011 2:02 PM
To: www-dom@w3.org
Subject: Improving the DOM; rev 2

Before: http://lists.w3.org/Archives/Public/www-dom/2011OctDec/0140.html

I forgot to explain before that we do not want to expose these methods
where they do not make sense. The current DOM has that, but I do no think
that is a particularly good design, and it is not a design we have used
elsewhere in the platform. Java and its casts are not a concern for the
platform.

It seems however people do not want to restrict these methods so far you
get limitations. Taking that into account I think this is the API you end
up with:

union ContentNode = DOMString Node;

Document / DocumentFragment / Element

prepend(ContentNode...)
append(ContentNode...)

DocumentType / Element / CharacterData

before(ContentNode...)
after(ContentNode...)
replace(ContentNode...)
remove(ContentNode...)

The next question is whether we should impose restrictions on these
methods at the IDL or method implementation level. E.g. appending a
DocumentType to Document can be fine, but appending it to Element is never
fine. Also currently you know that appendChild(DocumentFragment) on an
Element is going to work. With these vararg methods you do not, unless the
arguments are restricted at the IDL level, or otherwise at the method
implementation level. I no longer feel strongly where we do this, but I
believe Ojan had some concerns with respect to performance.

As to what these methods return, we should probably go with chaining. I'm
not a big fan, but it seems to be what all the cool kids are doing these
days, and the cost is negligible.


-- 
Anne van Kesteren
http://annevankesteren.nl/

Received on Friday, 18 November 2011 16:48:23 UTC