If your strings are really quite long, and you want all characters in groups of 3, then using tr/// first is ~50 times quicker: 

$x =~ tr[A-Za-z][]s; 
$x =~ s[(.)][$1 x 3]ge;

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In reply to Re: More efficient way to truncate long strings of the same character by BrowserUk
in thread More efficient way to truncate long strings of the same character by kurtis

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