in reply to How to split_and_pad string to n-th chars pieces with one regular expression?

Maybe I misunderstood the problem, but I'd try:

$txt =~ s/(.{1,3})/sprintf"%03s\n",$1/ge;

Update: missed the "empty string" part:

 ...
 $txt =~ s/(.{1,3}|^$)/sprintf"'%3s'\n",$1/ge;
 print $txt;
 ...

[download]

Regards

mwa

In Section Seekers of Perl Wisdom