[uf-new] Measurement brainstorming

[Manu Sporny]

Chris Newell wrote:
>> Note that I said "or whatever is [the] standard for representing
>> square-metres".
> 
> I'm not sure there is a standard for representing the superscripts 
> used within SI units using plain text.
> 
> We may have to specify something.

These are all good discussions, but I'm afraid that the second we get
into "We might have to specify something", we're going to get into
philosophical debates about how we represent prefixes, units and the
combinations thereof... thereby killing the discussion :)

In an attempt to avoid those philosophical debates, let's build on the
work of great people. Namely, the ISO and SI standards of measurement
used by the international community. I have put up Straw Man 2 on the
wiki in an attempt to outline basic markup that hmeasure could support:

http://microformats.org/wiki/measure-brainstorming#Straw_man_2

The Strawman includes the following new concepts:

- The proposal only uses abbr to avoid the "but the parsers are going to
  be so complicated!" argument. Let's focus on what we can represent
  using <abbr> - what we can support in <span> will naturally come out
  of that discussion.
- This is a first cut and is missing things like measurements for
  "cups", "feet", etc.
- SI-prefixes should be used when applicable.
- It attempts to simplify and focus the discussion on <abbr>

-- manu