date stuff in gnucash

[Robert Graham Merkel]

James LewisMoss writes:
 > 
 > 
 > src/scm/date-utilities.scm
OK, I added some stuff to support "relative dates" (which really
covered both "relative" and "abstract dates" to this file a while ago.
It hasn't been used much (until I/we update reports to use it).

 > src/scm/srfi/srfi-19.scm
 > 
 > srfi-19.scm doesn't contain all of the srfi #19 example implementation
 > and I was wondering why.
 > 
Unsure, I haven't really touched this stuff.

 > Anyway.  Here's the notes I have so far on what I need:
 > 
 > Types of dates:
 > 
 > Abstract: Not a real date or relative date.  This is for things like
 >  "The last monday in a month".  It's a date, but it's not a real
date.
 >
 > Relative: A date diff.  "Two weeks later".  "Two weeks earlier"
etc.
The difference between "abstract" and "relative" isn't quite clear to
me.

Both of them remain abstract until you give them an absolute date (or
at least part of an absolute date).

Additionally, what kind of arithmetic operations do you expect to be
able to do on "abstract" and "relative" dates?  It gets real complex,
real fast.

------------------------------------------------------------
Robert Merkel	                           rgmerk@mira.net

"We are excited and optimistic about its usage going 
forward and, yes, we can teach penguins the military 
close-order drill", Mark Norton, US Department of Defense. 
------------------------------------------------------------