20407 2012-12-16 03:52:10 +0000 allow attributes to have different types for their getter and setter 2012-12-30 23:23:51 +0000 1 1 1 Unclassified WebAppsWG WebIDL unspecified PC All NEW P2 normal --- 1 cam cam annevk bruant.d bugs ian jackalmage mike public-script-coord robin waldron.rick public-webapps-bugzilla oldest_to_newest 80248 0 cam 2012-12-16 03:52:10 +0000 http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2012-December/038362.html Maybe syntax like: attribute FileList? set (FileList? or sequence<Blob>) files; would work. 80249 1 bugs 2012-12-16 13:37:15 +0000 Feels ugly to me. Reminds me of PutForwards. 80256 2 robin 2012-12-17 10:26:07 +0000 (In reply to comment #1) > Feels ugly to me. Reminds me of PutForwards. Is it the syntax or the feature that you find ugly? If it's the syntax, we can certainly bikeshed it, e.g.: attribute FileList?/(FileList? or sequence<Blob>) files; and many other variants. But I don't think that we can dodge the fact that the feature itself represents a genuine need. 80257 3 bruant.d 2012-12-17 10:32:34 +0000 (In reply to comment #1) > Feels ugly to me. I think one not ugly way would be to have one super-type and all types used in the getter/setter use this super-type. But retrofitting a super-type after things are already deployed on the web doesn't feel like realistic. 80258 4 bugs 2012-12-17 10:55:48 +0000 (In reply to comment #2) > Is it the syntax or the feature that you find ugly? The feature. You set property to [ objectOfTypeA ], yet you get back [ objectOfTypeB ]. 80259 5 annevk 2012-12-17 12:24:37 +0000 We already do type conversion, I don't really see how this is different. 80271 6 bugs 2012-12-17 14:59:10 +0000 This would not be conversion, but creating new objects from the data passed to setter. 80292 7 jackalmage 2012-12-17 17:32:13 +0000 (In reply to comment #6) > This would not be conversion, but creating new objects from the > data passed to setter. I believe Anne means that a setFoo/getFoo pair, where setFoo accepts a wider variety of things but getFoo returns a specific type, is already possible, acceptable, and widely used. Thus, why is it unacceptable to do the same with an attribute? 80708 8 ian 2012-12-30 05:00:45 +0000 It's even done with attributes, e.g. anywhere we use PutForwards. This just seem like a variant on that. 80716 9 bugs 2012-12-30 14:02:35 +0000 Exactly. As I said in comment 1, reminds me of PutForwards. And some people think (I'm certainly not the only one) that use of PutForwards is bad API design. 80740 10 cam 2012-12-30 23:23:51 +0000 If [PutForwards] is bad, I would say it is due to it being not obvious what the actual property being changed is, not because it has asymmetric get/set types.