I may not be on-target with what you want but....

If you just want to increment increase/decrease dates by 1 I would suggest doing date math.

dDateVal = dDaveVal + 1

If you have to work with a string as a source, you could convert it to date first. For example cteststr = "2019-12-31"

ddateval = DATE(VAL(SUBSTR(cteststr,1,4)), VAL(SUBSTR(cteststr,6,2)), VAL(RIGHT(cteststr,2))) ddateval = ddateval + 1

(the above assumes you can ALWAYS really on the format to be "YYYY-MM-DD" - with no spaces - aka Feb 5, 2019 would be 2019-02-05)

And then if you need it as a string coming out:

cNewStr = str(year(ddateval), 4) + "-" + strtran(str(month(ddateval),2), " ", "0") + "-" + strtran(str(day(ddateval),2), " ", "0")

(I put the "STRTRAN" in there to force the day result to a 2-character 0-filled value)

-Charlie

On 7/17/2016 12:28 PM, Gene Wirchenko wrote:

Hello:

 I write a logic/math puzzle each week.  They appear in my blog 

(http://genew.ca/) and two local newspapers.

 Here is the latest problem:

 "Consider a date in YYYY-MM-DD format.  What is the next date 

where all eight digits will be different?"

 I solved this by hand.  I decided to verify my solution with a 

program. I often cook up something in GW-BASIC, but since VFP has date functions, I decided to go with it.

 It was very easy to set up the framework of the loop.  What threw 

me for a loop is how to check that all of the digits are different. I ended up converting the date to string with dtos() and then testing the string with a rather ugly-looking condition. Is there something faster?

[snip]