Re: [touch-events] Spec should be explicit on whether the of elements in TouchLists is relevant (#13)

On 11/05/2015 20:07, Rick Byers wrote:
> I don't think we'd ever want to leave gaps no. We should test to see if
> all existing implementations maintain order in the simple case of no
> touchstart/touchend. If so, that might at least be worth a note - with a
> warning saying you shouldn't rely on it. The fact that a site was relying
> on this caught us by surprise (though it's of course not surprising in
> retrospect) - seems like the sort of thing worth documenting somewhere
> unless at least one major implementation wants to take the hit of
> intentionally shuffling the ordering.

Ah, so the site was relying on the order/index remaining the same 
during, say, a touchmove when no fingers were added/removed? Ok, that 
kind of makes sense, though conceptually, you would then still need to 
include handling code that DOES look at the actual unique IDs as soon as 
a touch is added/removed, which then begs the question why they don't do 
that in all situations anyway...

If I were hardline (and well, I don't have a browser/compat issues to 
worry about personally), I'd say that the devs are relying on an 
undocumented "feature" which is conceptually wrong, and - if the number 
of sites that do this is small - it could be addressed with 
evangelism/outreach? Do we have an idea of how many sites, roughly, use 
similar assumptions in their code?

P
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Patrick H. Lauke

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