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Re: Why ignoring unknown mandatory constraints is not stupid

From: Jan-Ivar Bruaroey <jib@mozilla.com>
Date: Mon, 18 Nov 2013 15:53:47 -0500
Message-ID: <528A7E5B.4080207@mozilla.com>
To: Harald Alvestrand <harald@alvestrand.no>, public-media-capture@w3.org
On 11/18/13 3:03 PM, Harald Alvestrand wrote:
> On 11/18/2013 05:55 PM, Jan-Ivar Bruaroey wrote:
>> On 11/16/13 7:50 AM, Harald Alvestrand wrote:
>>> Because a mandatory constraint saying "3D camera" means "I want a 3D
>>> camera".
>> I understand. You'll refuse lots of users who have 3D cameras to avoid
>> dealing with the unknown. You, the programmer may be happy
>> (initially), while many users are unhappy. That's my problem. If you
>> don't see that trap, then many programmers won't either, and fall in
>> it. I thank you for demonstrating this.
> I don't think personalizing our disagreement is going to get us very far.
> It's plain that we disagree. I don't see any sign that one of us is
> doing very well in convincing the other.

My apologies, I meant no disrespect. I only sought to highlight the difficulty of this issue. Hopefully it is clear from context that the insult would have been to say "then many programmers would figure it out anyway", which is the opposite of what I said. I hold your views in the highest regard, and I will strive to communicate better in the future.

>> If he was happy with getting a 3D camera some of the time, he
>> could have used an optional constraint;
>> Saying programmers should always use optional constraints is no
>> solution, just like putting a working elevator adjacent to an open
>> elevator shaft is no solution (because the problem isn't just "How do
>> I get down now?" but "Entering absentmindedly is dangerous").
>> The problem with mandatory constraints is that they work too well,
>> falsely over-constraining in the unknown case, for no good reason to
>> boot (apps aren't melting today). So lets change them not to do that,
>> without breaking or abandoning them in the cases they do work.
> It's the "for no good reason" part I just plain disagree with.

OK good, because I will concede that an app may have good reasons. I just think this decision must be explicit in the app, not implicit in our interface, and that the default must be one that doesn't over-constrain the user experience (since the user is unable to affect the JS).

.: Jan-Ivar :.
Received on Monday, 18 November 2013 20:54:15 UTC

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