- From: Maciej Stachowiak <mjs@apple.com>
- Date: Wed, 19 Mar 2008 00:23:45 -0700
- To: Maciej Stachowiak <mjs@apple.com>
- Cc: Cameron McCormack <cam@mcc.id.au>, "Web APIs WG (public)" <public-webapi@w3.org>
On Mar 19, 2008, at 12:08 AM, Maciej Stachowiak wrote: > > ECMA-262 actually allows typeof to return anything at all for host > objects (which all of the DOM binding objects are). So it would not > be an ECMA-262 violation, technically, for an uncallable object to > give typeof == 'function', but I do think it would be a bad idea. > > In WebKit we currently follow the ECMA-262 callability-based > approach even for host objects, but not all web engines do. For > example, I believe that in Trident, NodeLists are callable but give > a typeof result of 'object' instead of 'function'. Alexey points out that we have had a bug filed because we report 'function' in this case: <http://bugs.webkit.org/show_bug.cgi?id=14547>. But it's not really clear if the IE behavior of being callable but reporting typeof == 'object' is required for compatibility (it is clear that NodeLists actually being callable is). There is much more discussion in the bug. Regards, Maciej
Received on Wednesday, 19 March 2008 07:24:25 UTC