On Thu, 01 Aug 2013 17:57:20 +0100, Tab Atkins Jr. <[email protected]>
wrote:
HTML is the Web's serialization format *for HTML, and other text-like
things*. As Kornel's example shows, HTML is *not* well suited to
holding key/value pairs or the like;
The ugly part is current lack of support for nested groups of metatags,
but HTML is pretty good at nesting in general, so this can be fixed easily
(I've proposed <metagroup> and <permission> in passing).
OTOH JSON is by design set in stone, so you can't relax parsing even to
fix the merge-conflict-inducing trailing comma, you can't add language
attribute to values, you can't add proper comments.
Here's a very interesting post about hacking JSON format, motivated by
pains of using JSON for configuration:
http://fadefade.com/json-comments.html
Comments are irrelevant for data serialization/exchange when JSON is spit
by software (and this is where JSON shines), but become a necessity in
files that humans have to carefully maintain.
When files are written by hand (and config files most often are) people
can abuse the syntax. The comment hack proposed in aforementioned article
makes JSON-with-comments incompatible with ES5 JSON and turns
underspecified quirk and implementation detail into de-facto standard.
JSON left out comments deliberately to avoid deteriorating by having a
hacky extension point, and now a hacky extension point has been found...
you have to hack them in via ugly
<meta> values, and you don't get any of the benefit of the rest of
HTML, because <meta>/<link> *is all you're doing*.
Actually, if I could define app's metadata and web components all in one
file that would be awesome:
<link rel="import manifest" href="/">
(and for added awesomeness I'd make that file my homepage, so I can have
self-contained 1-request web app, and subpages that get the manifest and
components from the page that is most likely to be cached).
This is quite different from Templates, because those are actually
leveraging HTML, and so using HTML as the delivery format as well just
reduces impedance mismatch. I don't think that applies here. JSON is
the way the web does key/value transmission.
JSON is fantastic for bare key/value transmission (uncommented,
unlocalized automatic data dump), but manifest is not just a basic
key/value transmission. Locales tree-patching-dictionary in the spec shows
that manifest already has impedance mismatch with JSON data model.
--
regards, Kornel
