Le 25/03/2013 20:00, Boris Zbarsky a écrit :
On 3/25/13 2:47 PM, David Bruant wrote:
For the latter case, a scoping trick might work. In essence, on* code
could run within a scope "located" between the code scope and the
global scope.
It already does: the scope is the element, with some more
complications as to what's on the scope chain above that.
I wasn't aware of that, but I see it now. Step 6 of:
http://www.whatwg.org/specs/web-apps/current-work/multipage/webappapis.html#event-handler-content-attributes
(Lexical Environment Scope stuff)
We could complicate the scoping setup for event handlers even more, of
course. Would any UAs actually be willing to implement that (given
that e.g. Chrome doesn't even implement the current, simpler, scoping
setup sanely)?
Any info on why they don't implement the spec scoping rules?
Is it going to be a case of de-facto standard too?
For the former case, things cannot be as easy as naively inserting an
intermediate scope, because the function definition is somewhere else,
but maybe we can get away with an equivalent trick. Thoughts?
I can't see any equivalent tricks given the scoping rules in JavaScript.
Basically, either UAs that currently implement window.event remove it
or it's clearly required for web compat and hence needs to be
specified so other UAs can implement it. I don't see any other sane
options; do you?
Only an insane option. Sharing as food for thoughts:
when about to call a function from an eval'ed on* attribute string,
change the function's [[Scope]] to contain an extra scope with an
"event" variable. Restore the [[Scope]] to its original value when the
frame is dropped.
But of course, as soon as I talked about changing [[Scope]], I
definitely fell in the "insane" category as I warned :-/
Since that case apparently requires window.event, no need to add extra
work on on* scoping, I guess.
If you want specific site examples www.ocn.ne.jp (on "mobile" only,
natch, thanks to only testing in WebKit) is the most recent one I came
across.
Is it the on* case? (how do you test for "mobile only"?)
It's using event handlers, yes. You test for "mobile only" by loading
the site in Firefox on some desktop platform and Firefox on Android
and observing that the site is UA-sniffing and sending different
content, and that the site sent to desktop browsers works in Firefox
but the site sent to "mobile" browsers does not.
Now I realize my question was stupid...
David
