357792 - Investigate whether XML Events could be implemented as an extension

Status: RESOLVED WONTFIX

(Core :: XML, defect)

Description

[Olli Pettay [:smaug][[e-mail]]]

Since XML Events is currently used only by extensions, I'd like to
try to move it to be an extension too.
The idea is to provide XTF-like extension mechanism for attributes too.
(But I'm not yet quite sure how.)

Comment 1

[alexander :surkov (:asurkov)]

(In reply to comment #0)
> The idea is to provide XTF-like extension mechanism for attributes too.
> (But I'm not yet quite sure how.)
> 

Olli didn't say but I guess he means too we need it to support xforms stuff (attribute based repeats (for example bug 340515) and ability to use custom namespace elements with xforms model - bug 306526).

Therefore I guess this has one requirement, it is element should be able to have both XTF binding and like XTF attribute binding (let call me XAF).

Other non like XTF issue is attribute binding should be unbound if attribute is removed and bound if attribute is appended. Also what will be if element has two attributes that assumes to use two different XAF bindings?

Comment 2

[Olli Pettay [:smaug][[e-mail]]]

(In reply to comment #1)
> Olli didn't say but I guess he means too we need it to support xforms stuff
> (attribute based repeats (for example bug 340515) and ability to use custom
> namespace elements with xforms model - bug 306526).

attribute based repeats are something way more complex, XTF
for attributes won't fix that.


> 
> Therefore I guess this has one requirement, it is element should be able to
> have both XTF binding and like XTF attribute binding (let call me XAF).
> 
> Other non like XTF issue is attribute binding should be unbound if attribute is
> removed and bound if attribute is appended. Also what will be if element has
> two attributes that assumes to use two different XAF bindings?
> 

"Attribute bindings" won't be bound to elements, but to attributes.

Comment 3

[aaronr]

I don't like the practicality of this.  Version maintanance is a pain the arse for enterprise users (the target audience for almost anything xml based).  What's going to happen when extensions become dependent on versions of other extensions?  XForms needs version 'x' of xmlevents but x+v needs version 'y'.  Does Mozilla have install solutions for this scenario already?  I guess we could give the user the option of ignoring any install errors and just pray things work well together.

Plus, if we can't keep xmlevents in the default build, how are we ever going to get xforms there?  Or any of the other new XML based technologies?  This is us (Mozilla) betting that all of the other XML-based technologies can also be implemented as extensions?  And who is going to support the XTF changes once they are made?  It'll make extensions even more dependent on a practically-unsupported component.

I have no problem with the concept.  I understand that xmlevents is overhead that isn't often utilized (yet).  But this would introduce potential issues that we don't currently have just to experience a practically insignificant gain (IMO).

Comment 4

[Olli Pettay [:smaug][[e-mail]]]

Attachment: xtf attributes & xml events implemented using xtf

Just attaching the patch so that I don't lose it.

Comment 5

[Anne (:annevk)]

XML Events is long gone.