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 FileMaker Pro Custom Functions

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IdentifyDupes ( Original_List, i, Dupes )

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  Average rating: 4.8  (30 votes)
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Jon Rosen, ErgoSoma

Returns only unique duplicate values from a list. Most of the time we're trying to identify the unique values in a list. This CF returns the values in a list that have duplicates.

Sample Input:
IdentifyDupes ( Apples
Grapes ; 1 ; "" )
Sample Output:

 Then copy & paste into FileMaker Advanced's Edit Custom Function window.

Click here to copy To Clip Manager if you have myFMbutler's Clip Manager installed


Usually, we're trying to identify the unique values in a list. This custom function does the reverse. It returns a unique list of duplicate values from a list (one value per duplicate).

Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

This is my Custom Function and I want to edit it


This function have some issues, because when you try to past it into custom function, there are warnings about some variables that aren't identified.

1. How is possible to have "1" or empty "" as function parameter?
2. The function parameter is List_of_Values, but you use a variable called Original_List.


caps, Portugal
February 25, 2012 3:12am

Hi found the problem, the tittle is wrong should be:

IdentifyDupes ( Original_List ; i ; Dupes )

caps, Portugal
February 25, 2012 3:22am

Thanks for pointing that out. I changed the title.

Jon Rosen, Florida
February 25, 2012 6:29am

Thanks for sharing!

March 08, 2016 2:05pm

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