validation scripting

Here's the bare bones of a validation script I'm working on.  Steps in
brackets [] represent functions that don't seem to exist in FMPA:

* set field ( titles::t_idv ; titles_lookup::t_idc )
* [ check validation of t_idv ]
* If [ titles::t_idv does pass validation ]
*  set field ( titles::t_id ; titles_lookup::t_idv )
*  commit records
*  halt script
* EndIf
* If [ titles::t_idv does not pass validation ]
*  set field ( titles::t_idv ; titles_lookup::t_idc&"a" )
* EndIf
* [ check validation of t_idv ] 
* If [ titles::t_idv does pass validation ]
*  set field ( titles::t_id ; titles_lookup::t_idv )
*  commit records
*  halt script
* EndIf

where:

# titles_lookup = another table occurance of titles
# titles::t_id = text field, must be unique
# titles::t_idc = calc field that generates a text string by grabbing
characters from another text field
# titles:t_idv = text field, must be unique

I want to create unique values for t_id.  There doesn't seem to be a
function for testing validation.

My idea was to generate an ID (t_idc), stick it in a field (t_idv),
and check to see if it already exists in any record by using a value
list.  The value list consists of all values in t_id.  If it's not in
the list (does pass validation), then stick it in t_id and save it. If
it is in the list (does not pass validation), then append "a" to the
end of the ID and check it again.  This way the ID is held out of the
value list for comparison purposes, and isn't added to the list if
it's in there already.  It seems like there ought to be a way to do
this using the ValueListItems function.

thanks in advance

-- 
FW

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