- From: Ian Hickson <ian@hixie.ch>
- Date: Wed, 8 Jul 2009 02:20:33 +0000 (UTC)
- To: Simon Pieters <simonp@opera.com>, Philip Taylor <pjt47@cam.ac.uk>
- Cc: "public-html@w3.org" <public-html@w3.org>
On Wed, 10 Jun 2009, Philip Taylor wrote:
> Ian Hickson wrote:
> > On Tue, 19 May 2009, Simon Pieters wrote:
> > > The spec doesn't call out NaN and Infinity for globalAlpha. I think
> > > globalAlpha should be handled consistently with the other canvas
> > > attributes and not throw an exception.
> > >
> > > http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-context-2d-globalalpha
> >
> > The spec says:
> >
> > Unless otherwise stated, for the 2D context interface, any method
> > call with a numeric argument whose value is infinite or a NaN value
> > must be ignored.
> >
> > ...and doesn't appear to contradict this in the definition of
> > globalAlpha. Am I missing something?
>
> Unless I'm missing something: globalAlpha isn't a method call.
>
> ("Common conformance requirements" differentiates "DOM attribute"
> assignment from "method" calling, so I presume that distinction is real,
> and the bit you quoted from the spec only talks about method calls.)
Oops, yes. My bad.
On Wed, 10 Jun 2009, Simon Pieters wrote:
>
> 2.2.3 Common conformance requirements for APIs exposed to JavaScript
> says to throw NOT_SUPPORTED_ERR.
>
> Since the spec says whether to throw or not for everything *but*
> globalAlpha for the 2d context, the spec would be clearer if the part
> you quoted was zapped and that you call out anything that's different
> from 2.2.3. The spec is hard to follow when there are different "unless
> otherwise stated" for different parts of the spec.
Ok, fixed, though I didn't remove the bit about method calls.
--
Ian Hickson U+1047E )\._.,--....,'``. fL
http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,.
Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Received on Wednesday, 8 July 2009 02:21:13 UTC