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do not deprecate synchronous XMLHttpRequest

From: Gregg Tracton <tracton@gmail.com>
Date: Thu, 05 Feb 2015 14:58:49 -0500
To: <public-webapps@w3.org>
Message-ID: <D0F935A9.51C64%tracton@gmail.com>
I disagree with deprecating synchronous XMLHttpRequest:

1) it is not upward compatible & so can break numerous sites.
Many websites do not have active development, and framework updates
that fix this are even slower to roll out to web apps.  Many web
app clients would much prefer a sub-optimal experience than a
broken website.

2) A better way to approach this might be to respect the async=false
setting but have the browser move the script thread to another thread which
is blocked until the jax (not ajax anymore) completes.  Make the browser do
the heavy lifting so scripts remain simple.

3) Loading long chains of on-demand content becomes unnecessarily complex.
Example: a config file that specifies URLs for column headers which specify
 URLs for content requires 3 nested .success handlers.  With async=false,
 one can simple write those sequentially.

4) Have it been considered if jQuery can create a work-around to simulate
async=false?  If not, do not deprecate, as there will be even more
browser-specific code splintering.

5) When data loads slowly, many sites will show a "please wait"
view anyway, which disables useful interactions, so how much value
does this deprecation add to usability?

6) Do you really want script writers to deal with scroll events while
an ajax is outstanding?  That seems to be beyond the ability of a plug-in
to handle in the general case. async=false really simplifies some tasks.

--Gregg Tracton, Chapel Hill, NC, USA
Received on Friday, 6 February 2015 08:45:18 UTC

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