Hi Monks! I am stuck with this, as I thought, simple task. Let's say I have some input string like 
testing 1234567 ........ aaaaaaaasssssss __________ ++++++++++ -------
+-- testing testing

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but I don't want to allow more than three similar chars one by one and I need the string to be modified to: 
testing 1234567 ... aaasss ___ +++ --- testing

[download]
I played with regex but have no idea how to identify similar chars. What is the best way to make this filter? It will be used on big strings, say a few megabytes.

In reply to Supress similar chars in the string by Lana

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