brendan at mozilla.org
Thu Oct 11 21:19:10 PDT 2007
On Oct 11, 2007, at 8:02 PM, Garrett Smith wrote:
>> If you want to apply or call a non-function
>> callable, use Function.apply(callable, thisp, argArray) or
>> Function.call(callable, thisp, arg1, ...argN).
> So these are equivalent?
> Function.call( aNonFunctionCallableObj )
We don't need to go back and forth -- I wrote essentially the same
thing, but included the optional arguments. The two expressions you
wrote are equivalent assuming the global object should bind to |this|
for both to be equivalent.
> If an object is invokable with arguments (), but not a Callable, it's
> impossible to type check. IE's call-like operation on with () is not
Why do you say that? There's no reflection of [[Call]] into the
language yet, so how can you tell?
(Don't rely on typeof x == "function" meaning x.[[Call]] exists --
browsers do not follow ES3 here, although we tried in SpiderMonkey
for years before throwing in the towel.)
> Microsoft often says that it is necessary to retain backwards
> compatibility. I would hope they would
You're barking up the wrong tree here. This is es4-discuss.
> Mozilla has this weird function-like thing, too, (only with
> document.all, which is not used much anymore)
As I keep saying, any reflection of document.all in an ES4 "DOM level
0 plus IE quirks" binding should indeed make (document.all is
Callable) => true.
>> I don't know what "BackCompat mode" means, but we do reflect
>> document.all if a script uses it without object-detecting it, and
>> only in such cases (since many well-written scripts fork based on if
>> (document.all) ... else ... tests and we want to run the else
> "CSS1Compat" -- standards mode
> "BackCompat" - quirks mode
> BackCompat supports document.all
No, you're mixing things up. As I wrote, our document.all emulation
has nothing to do with DOM specs or document.compatMode, and it works
irrespective of the latter's value.
> Mozilla really made document.all look like IE's weird
Like, yeah -- that was the point!
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