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 FileMaker Pro Custom Functions

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FindDuplicateCharacters ( string )

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  Average rating: 5.0  (1 vote)
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RealGrouchy, (self)

Returns True if the given string

Sample Input:
FindDuplicateCharacters ( "1234561"
Sample Output:

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


There are plenty of functions out there to find and manipulate unique or duplicate values within a given list of ΒΆ delimited values, but I couldn't find anything that looked for duplicate *characters* within a string. I whipped this one up.

It's simple enough but I figured I'll upload it for the next person who goes looking for it. It took me more time to look for it than to recreate it because I assumed there *must* be one out there! There probably is one and I just didn't use the right search terms.

- RG>

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


would be better if

now this function get into infinite loop if parameter is shorter than 1 character (then get ? as result).

esc, tokyo
June 11, 2018 8:30pm

Good catch. I've submitted the change!

- RG>

RealGrouchy, Ottawa, Canada
June 11, 2018 11:15pm

If the characters in the string are limited to a specific range/set of characters that you can specify explicitly, e.g. 0-9a-zA-Z, then you can write this in a closed form without needing recursion.

alphanum = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

Length(Filter(alphanum; string)) <> Length(string)


Tom Hays, Virgina, USA
August 17, 2018 6:00am

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