Re: IndexedDB: undefined parameters

[João Eiras]

On Tue, 09 Oct 2012 20:37:36 +0200, Alec Flett <alecfl...@chromium.org>  
wrote:

On Tue, Oct 9, 2012 at 11:12 AM, Boris Zbarsky <bzbar...@mit.edu> 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:

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);


According to the issue here, it would have to be written as

$ if (range && direction) return source.openCursor(range, direction);
$ else if(range) return source.openCursor(range);
$ else return source.openCursor(range);

which is a bit annoying, specially if the parameters are being already  
passed to a wrapper function, e.g.:

$ function open_cursor(range){
$  return os.openCursor(range, 'next');
$ }
$ open_cursor();