question about how to update an item in a field in batch mode

[Jeanne A. E. DeVoto]

At 5:46 PM +0000 1/21/2008, Peter Alcibiades wrote:
>So what I am trying to do is go through the sales field using the number and
>description from each line, one after the other, and match each line against
>the record for that product in the stock field, then if there is a match,
>knock down the no in inventory in the stock field, which is item 5,  by 1.
>
>If I could make it work, the result of running it in the above instance would
>just be that the no in stock would fall to 99 and 149.
>
>The sticking point is how to do this match and decrement using repeat.
>
>I can do it easily when dealing with it one record at a time - when there is
>only one record in the field, so there is no repeat loop.  But I'm having
>great trouble figuring out how you do it when you have to run through a
>series of records from the first field one after the other against the second
>field  Part of the difficulty may be the thing that was referred to earlier
>on the list, that you cannot modify the repeat for variable.


Here's one way:

set the itemDelimiter to tab
put field "Sales" into mySales -- not strictly necessary but speeds things up
-- collect the info about how many of each thing were sold today:
repeat for each line thisSale in mySales
   add 1 to soldThings[item 2 of thisSale]
   -- this builds an array where the keys are the item descriptions
end repeat
-- now update the Stock list to account for all items sold:
put field "Stock" into myStock -- again, for speed
repeat for each key thisThing in soldThings
   -- figure out which line of the stock list is the record for this thing:
   put lineOffset(tab & thisThing & tab,myStock) into thisThingLineNumber
   -- and subtract the total sold today from the number of this thing in stock:
   subtract soldThings[thisThing] from item 5 of line 
thisThingLineNumber of myStock
end repeat
put myStock into field "Stock"
-- 
Jeanne A. E. DeVoto, Transcript Language Curmudgeon
revolution at jaedworks.com
http://www.jaedworks.com