I'll agree that it is a bit on the confusing side, I'm pretty sure that there's a point in the spec that it indicates that 'null' is how to represent a not provided key but supporting 'undefined' would make it simpler to work with the API. The problem I can see with that is there are several shipped implementations of the spec that this would break for (if I recall correctly IE10 will raise a DataError on undefined but not null).
Aaron Powell MVP - Internet Explorer (Development) | FunnelWeb Team Member<http://funnelweblog.com/> http://apowell.me<http://apowell.me/> | http://twitter.com/slace | Skype: aaron.l.powell | Github<http://github.com/aaronpowell/> | BitBucket<http://hg.apwll.me/> From: [email protected] [mailto:[email protected]] On Behalf Of Alec Flett Sent: Wednesday, 10 October 2012 8:52 AM To: Boris Zbarsky Cc: [email protected] Subject: Re: IndexedDB: undefined parameters On Tue, Oct 9, 2012 at 11:37 AM, Alec Flett <[email protected]<mailto:[email protected]>> wrote: On Tue, Oct 9, 2012 at 11:12 AM, Boris Zbarsky <[email protected]<mailto:[email protected]>> wrote: On 10/9/12 1:52 PM, Joshua Bell wrote: The IDB spec does not have [TreatUndefinedAs=Missing] specified on openCursor()'s arguments (or anywhere else), so I believe Chrome's behavior here is correct. It looks correct as the spec is currently written. It's not clear to me why the spec is written the way it is. It could just as easily define that if the "any" value is undefined, it's ignored. Or it could use [TreatUndefinedAs=Missing], indeed. I have to say, as a developer it can be really frustrating to write abstractions on top of APIs that behave this way, when you want to say something like: Someone asked me to clarify: by "this way" I meant "where passing undefined is different than calling without the parameter" - meaning that in general, APIs should behave the same if you call foo(undefined) as if you called foo(). Otherwise it's notoriously hard to write anything functional (in the CS sense) around it. Alec var direction; var range; if (condition1) direction = 'prev'; else if (condition2) direction = 'prevuniq'; if (condition3) { range = range1; else if (condition4) range = range2; return source.openCursor(range, direction); Alec
