World: r3wp

well, one thing I've wondered is how to add weeks, months, years, 
etc. to dates

Jarod - yes.

I like that function a bit more Graham, I basically think I understand 
what that is doig

the ".." is synatactic sugar.

doing

having to write a function to do that is a pain, but I can probably 
live with it, knowing exactly what it is doing

I mean, all languages have quirks

hehe

I don't use substr much at all either .. but your complaint was one 
I also felt :)

I mean, there are times when parse will work

but honestly, I could actually see parse having the ability to substring

I am surprised it doesn't

how can you do more with dates than just add days to them?

So why doesn't someone write a .r file you can run that adds common 
functions for other languages (i.e. basic.r would have 'substr,

I guess there are several ways it could be implemented

user.r ?

putting it in user.r?

Someone (or a group of someones) should write a .r file for the common 
languages (i.e. basic.r would include 'substr, 'peek, 'poke, etc.; 
rexx.r would include 'mid, etc.).  That way, new users from other 
languages could move into Rebol with the knowledge they already have. 
 Of course, the script flow would be different, but their favorite 
functions would be available, and they could see how to implement 
their favorite functions natively using 'source.  There could also 
be a %c.r for those coming straight from C. :-)

and things like .. cd, dir and other common dos functions

Ah, but to implement dos.r, you would have to remove about 90% of 
Rebol's functionality ;-)

Just kidding...I was being mean about how bad DOS really is as a 
scripting language. :-)

Jarod...I guess you are asking about how to add to dates.  Here is 
an example:

>> b: now/date
== 27-Mar-2006
>> b/month: b/month + 6
== 9
>> b
== 27-Sep-2006

that adds months, what about weeks?

hmm

>> week: 7 ;Defining a "constant" here
== 7
>> b/date: b/date + (6 * week)
== 8-Nov-2006

hmm

I guess I didn't need to use 'b/date, just 'b would have worked.

>> b: b + (6 * week)
== 8-Nov-2006

yeah, but I mean, let's say I took two dates, and I wanted to know 
the number of months between them, the date/month thing doesn't work

maybe if I take the number of days and divide by 12

use 'difference to get the difference between two dates

A pretty close estimate is the following: date2 - date1 / 365.25 
* 12

interesting

difference

so that returns results in hours?

Difference returns the difference in hours.

yeah, and I could continue converting that

hmm

>> ( difference now/date 1-Jan-2006 ) / 24:00 / 30
== 2.86666666666667

still dividing by 30 isn't exactly accurate

all still very interesting, though

rebol still has better date management, than say perl for example

Over a period of time, dividing by 365.25 and multiplying by 12 is 
pretty accurate.

365.24 is more accurate, though  ^.-

Thanks, Izkata.

I start with 2 dates:
>> d1: now/date
== 28-Mar-2006
>> d2: 1-1-08
== 1-Jan-2008
To calculate the number of months between them:
>> months: (d2/year * 12 + d2/month) - (d1/year * 12 + d1/month)
== 22
>> if d1/day > d2/day [months: months - 1]
== 21
To calculate the number of remaining days:
>> d1/month: d1/month + months
== 24
>> d1
== 28-Dec-2007
>> d2 - d1
== 4


So there are 21 months and 4 days between the 2 dates (if I calculated 
right).

The situation with REBOL is, that you can do almost anything with 
it. If someone should document that, she could start now and not 
be finish, before she turned 100 years old. I saw myself as a very 
competent programmer with many years of experience in many different 
languages, before I discovered REBOL. It took me a year or so do 
'get' REBOL, because it's so different. I could very fast write simple 
things, but to get in under the skin of REBOL takes some time. In 
some way REBOL is a bit hard at first, and it takes some time to 
'get' it, then suddently it become very easy.

As a function:

monthdiff: func [d1 d2 /local months days] [
	months: (d2/year * 12 + d2/month) - (d1/year * 12 + d1/month)
	if d1/day > d2/day [months: months - 1]
	d1/month: d1/month + months
	days: d2 - d1
	reduce [months days]
]

Nice...