[whatwg] A tag for measurements / quantity?

Ian Hickson ian at hixie.ch
Thu Aug 27 17:30:23 PDT 2009

On Mon, 17 Aug 2009, Max Romantschuk wrote:
> Ian Hickson wrote:
> > I don't really understand the use case here. What problem would this be
> > solving? What do we have to demonstrate that this problem matters?
> It might well be that there is no problem.

Ok. Then I recommend we punt this to the next version.

> From a practical perspective it would be nice to have an unambiguous way 
> to mark up numerical constants in a document and thus allow a 
> straightforward way of doing conversions.
> Personally, the obvious use case for me is recipes. Even a relatively 
> simple one requires a lot of manual calculation to convert cups, pounds 
> and ounces into deciliters and grams. While some sites supply conversion 
> tools for this providing the semantic information straight in the markup 
> would allow conversions for any document.
> With the large majority of humanity doing cooking one could argue that 
> this would be genuinely useful. Then again, it's quite possible no one 
> would ever use this, and it would just end up cluttering the spec.

I can't imagine really seeing enough sites using this to make it worth it, 
but maybe our experience with <time> will show this kind of thing is used 
a lot.

On Wed, 19 Aug 2009, Jeremy Keith wrote:
> The problem statement on the microformats wiki page reads:
> "Measures (e.g. weights, sizes, temperatures) occur frequently on the 
> Web, they are constituted of a value a unit-measure and, in scientific 
> and technical contexts, an experimental uncertainty. These 3 elements 
> should be marked-up consistently across websites so that they can be 
> easily identified and acted upon (export, compute, convert) in 
> collaborative distributed applications.
> Unit-measures differ from locale to locale (e.g. Fahrenheit vs. Celsius, 
> pound versus Kilogram), making comparison and matching of offerings 
> difficult.
> The measurement microformat will enable unambiguous description of 
> physical quantities and thus provide a solid ground for data sharing and 
> automation in many areas."

This is begging the question. Just because a pattern occurs a lot doesn't 
mean that it should be marked up.

But I guess if the microformat is successful, we'll have the data we need 
for the next version of the spec.

Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'

More information about the whatwg mailing list