Re: atoms, molecules

["Simon St.Laurent" <simonstl@simonstl.com>]

At 12:38 PM 4/17/01 -0700, Kohsuke KAWAGUCHI wrote:

> > It seems as if regular expressions could be used not just for 
> validation of
> > typed content, but for fragmentation of typed molecules into smaller
> > atoms.  Instead of binding users to a particular (ISO 8601) date format,
> > this approach would let users provide their own rules for fragmenting date
> > strings into the parts we need for processing - year, month, day, etc.
>
>One of the problem of this approach is that you can't specify order
>relation and equality relation. And date/time is utterly useless without
>them (it is ironic that the current date/time types are also broken with
>respect to order/equality relation)
>
>How would you define 24hours=1day, or 2minutes < 150 seconds in your
>atom/molecule model?

Fragmentation is just a first step to getting usable parts.

I completely agree that this doesn't solve the entire problem, but it does 
open the way to other solutions.

What I initially had in mind was that programs using this information would 
include the logic needed to deal with 2min<150sec.  It also seems possible 
to create more complex rules inside of the type description which 
understood what the atoms meant (easier with numbers than letters, but 
we'll start there) and what their relationships were.

The first step, though, seems to be breaking the larger unit into smaller 
pieces so that we can at least get a handle on what is inside of it.  Once 
we have the parts, we can start talking about rules for processing the parts.


Simon St.Laurent - Associate Editor, O'Reilly and Associates
XML Elements of Style / XML: A Primer, 2nd Ed.
XHTML: Migrating Toward XML
http://www.simonstl.com - XML essays and books