[whatwg] canvas 2d's ellipse

[Rik Cabanier]

On Tue, Sep 17, 2013 at 1:27 PM, Ian Hickson <ian at hixie.ch> wrote:

> On Tue, 17 Sep 2013, Rik Cabanier wrote:
> > On Tue, Sep 17, 2013 at 11:31 AM, Ian Hickson <ian at hixie.ch> wrote:
> > > On Tue, 17 Sep 2013, Tab Atkins Jr. wrote:
> > > > >
> > > > > I'm not a fan of "sweep it under the carpet" bug handling,
> > > > > personally. It drives me crazy that JavaScript has no type
> > > > > checking, no argument checking, etc. So many bugs that should be
> > > > > caught at compile time, or at least at runtime when the code is
> > > > > reached, are instead caught only after careful testing.
> > > >
> > > > "Runtime when the code is reached" often actually means "Whoops! Now
> > > > the entire app's broken because I forgot to handle a silly
> > > > edge-case.". When there's an easy and obvious recovery strategy,
> > > > it's often much friendlier to authors to take it rather than force
> > > > them to handle errors.
> > >
> > > Usually in these cases the entire app is probably still broken --
> > > maybe with data corruption, even, or with confusingly bad behaviour.
> > > The only difference is that you have no idea where to begin looking.
> >
> > Ok, so what if *some* applications would be horribly broken. *Others*
> > will still stumble along or work perfectly fine. I'd rather have that,
> > than a completely broken page.
>
> Dramatically simplifying the situation here, we're saying that the
> available options are:
>
> A: All buggy applications fail to compile, because of static checking.
>    Cost to fix the bugs is low.
>
> B: All buggy applications break entirely when edge cases are hit.
>    Cost to fix the bugs is moderate.
>
> C: Some buggy applications break entirely when edge cases are hit.
>    Some buggy applications have data corruption!
>    Some buggy applications have merely graphical artefacts.
>    Cost to fix the bugs is high.
>
> I think option A is vastly superior, but since that's not an option,
> option B is preferable to option C.
>

You are speaking as a developer, not as a user of a web application.
Browser could offer a 'debug' more where they break on bad calls or output
messages to the console.
Once it's 'released', the runtime should be permissive.


>
> In reality, I don't think it's true that the Web always goes with C. If it
> did, there'd never be exceptions thrown by APIs, and exceptions are thrown
> all the time by APIs. Indeed, if it were the case that we had a philosophy
> of going with "muddling along" where possible, JavaScript wouldn't have
> syntax errors, or, much like CSS, it would have rules for recovering from
> them and would simply ignore syntactically invalid constructs. We don't do
> that. Instead, we chose the middle ground B most of the time.
>
> --
> Ian Hickson               U+1047E                )\._.,--....,'``.    fL
> http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
> Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'
>